Ford Fiesta Quiz
Body and Paint

Seats - Diagnosis and Testing

In this manual: Body and Paint
Service Information — 27Suspension — 48Transmission — 9Brake System — 52Steering — 21Engine — 140Manual Transmission, Clutch, Transfer Case and Power Transfer Unit — 48Exhaust System — 6Fuel System — 21Climate Control System — 58Instrumentation and Warning Systems — 26Battery and Charging System — 20Infotainment Systems — 41Lighting — 29Power Distribution — 11Electronic Function Group — 30Body and Paint — 275Frame and Mounting — 3
~30min read

DTC Chart: BCM

The diagnosis in this manual assumes a certain level of skill and knowledge of Ford-approved diagnostic procedures.
REFER TO: Diagnostic Methods (100-00 General Information, Description and Operation).


DTC Chart


Trouble Code Description Action
B1034:12 Front Left Seat Heater Element: Short to Battery GO to Pinpoint Test B
B1034:14 Left Front Seat Heater Element: Short to Ground or Open Circuit If the seat heater does not operate, GO to Diagnostic Test B. If the seat heater is always on, GO to Diagnostic Test D
B1036:12 Front Right Seat Heater Element: Short to Battery GO to Pinpoint Test C
B1036:14 Right Front Seat Heater Element: Short to Ground or Open Circuit If the heated seat does not operate, GO to Pinpoint Test C. If the heated seat is on all the time, GO to Pinpoint Test D.
B115A: 23 Front Passenger Seat Heater: Low Signal Level GO to Pinpoint Test C
B115B: 23 Front Driver Seat Heater: Low Signal Level GO to Pinpoint Test B
All Other Diagnostic Trouble Codes (DTCs) -
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Diagnosis and Testing).

Symptom Chart

Symptom Chart: Seats

The diagnosis in this manual assumes a certain level of skill and knowledge of Ford-approved diagnostic procedures.
REFER TO: Diagnostic Methods (100-00 General Information, Description and Operation).


Symptom Chart


Condition Possible Sources Action
Driver and passenger heated seats do not operate. Refer to Pinpoint Test GO to Pinpoint Test A
Seat Heater Inoperative/Operates Incorrectly - Driver Refer to Pinpoint Test GO to Pinpoint Test B
Seat Heater Inoperative/Operates Incorrectly - Passenger Refer to Pinpoint Test GO to Pinpoint Test C
Heated seat does not operate correctly - driver or passenger seat heater on with system off Refer to Pinpoint Test GO to Pinpoint Test D
Heated seat does not operate correctly - driver seat heats but heated seat indicator does not illuminate when pressed Refer to Pinpoint Test GO to Pinpoint Test E
Heated seat does not operate correctly - passenger seat heats but heated seat indicator does not illuminate when pressed Refer to Pinpoint Test GO to Pinpoint Test F
Heated Seat Indicator Stays On Constantly - Driver or Passenger Seat Heater Refer to Pinpoint Test GO to Pinpoint Test G

Pinpoint Test(s)

Driver and passenger heated seats do not operate.


Refer to Wiring Diagrams Cell 119 for schematic and connector information.

Normal Operation and Fault Symptoms

The heated seat system operates only with the engine running. When the driver or passenger heated seat switch (located in the instrument panel) is activated, it supplies a ground signal to the BCM. When the BCM receives the heated seat switch signal, it activates the corresponding (driver or passenger) heated seat relay (located in the CJB). When the heated seat relay is energized, voltage is supplied to the seat heating mats. The heating mats are directly connected to ground, completing the heated seat electrical circuit.

Possible Sources:

  • Fuse
  • Wiring, Terminals or Connectors
  • BCM

Visual Inspection and Preliminary Diagnosis

  • Make sure that CJB fuse 17 (15A) is in good condition.

DIAGNOSTIC TEST A: BOTH SEAT HEATERS INOPERATIVE - DRIVER AND PASSENGER
A1 CHECK THE DRIVER HEATED SEAT RELAY VOLTAGE
  • Disconnect: Driver Heated Seat Relay.
  • The ignition is on.
  • Action:
    Positive lead Measurement/Action Negative lead
    Driver Heated Seat Relay, Terminal 1. Ground

Is the voltage greater than 11 volts?
Yes GO to A2
No CHECK CJB fuse 17 (15A) is in good condition. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams Manual to determine possible causes of the short circuit.
A2 CHECK THE HEATED SEAT SWITCH GROUND CIRCUIT
  • Ignition OFF.
  • Disconnect: Driver Heated Seat Switch C2400.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2400-4 Ground

Is the resistance less than 3 ohms?
Yes GO to A3
No REPAIR the circuit.
A3 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Ignition OFF.
  • Disconnect and inspect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM connectors and all previously disconnected rear window heater system connectors. Make sure they are seated and latched correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.

Seat Heater Inoperative/Operates Incorrectly - Driver


Refer to Wiring Diagrams Cell 119 for schematic and connector information.

Normal Operation and Fault Symptoms

The heated seat system operates only with the engine running. When the driver or passenger heated seat switch (located in the instrument panel) is activated, it supplies a ground signal to the BCM. When the BCM receives the heated seat switch signal, it activates the corresponding (driver or passenger) heated seat relay (located in the CJB). When the heated seat relay is energized, voltage is supplied to the seat heating mats. The heating mats are directly connected to ground, completing the heated seat electrical circuit.


DTC Fault Trigger Conditions


Trouble Code Description Fault Trigger Conditions
B1034:12 Front Left Seat Heater Element: Short to Battery If the driver heated seat relay control circuit is shorted to voltage and the BCM attempts to activate the driver heated seat relay, this DTC sets and the seat does not heat.
B1034:14 Left Front Seat Heater Element: Short to Ground or Open Circuit If the driver heated seat relay control circuit is open or shorted to ground and the BCM attempts to activate the driver heated seat relay, this DTC sets and the seat does not heat (open circuit) or may heat only once (short to ground) until the ignition is turned off.
B115B: 23 Front Driver Seat Heater: Low Signal Level Sets when the BCM detects that the driver heated seat switch is active during an on-demand self-test or has been active for more than 2 minutes.

Possible Sources

  • Heated Seat Relay
  • Heated Seat Switch
  • Wiring, Terminals or Connectors
  • Heater Pad
  • BCM

DIAGNOSTIC TEST B: SEAT HEATER INOPERATIVE/INCORRECT OPERATION - DRIVER
B1 RETRIEVE THE BCM (BODY CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • The ignition is on.
  • Using a scan tool, perform the BCM self-test.

Is DTC B1034:12, B1034:14 or B115B:23 present?
Yes If DTC B1034:14 is present, GO to B7.
If DTC B1034:12 is present, GO to B6.
If DTC B115B:23 is present, GO to B4.
For information on all other diagnostic trouble codes (DTCs), REFER to the BCM DTC Chart.
No If the seat cushion and seatback heating mats do not operate, GO to B2.
If only the seat cushion heating mat does not operate, INSTALL a new driver seat cushion heating mat.
If only the seatback heating mat does not operate, INSTALL a new driver seatback heating mat.
B2 CHECK THE DRIVER HEATED SEAT (CC_SW_D_HSEATS) PID (PARAMETER IDENTIFICATION) OPERATION
  • Ignition OFF.
  • Using the diagnostic scan tool, view the BCM CC_SW_D_HSEATS PID while pressing and releasing the driver heated seat switch.

Does the PID agree with the driver heated seat switch state?
Yes GO to B9
No GO to B3
B3 CHECK THE DRIVER HEATED SEAT SWITCH GROUND CIRCUIT FOR OPEN
  • Ignition OFF.
  • Disconnect: Driver Heated Seat Switch C2400.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2400-4 Ground

Is the resistance less than 3 ohms?
Yes GO to B4
No REPAIR the circuit.
B4 CHECK THE BCM (BODY CONTROL MODULE) DRIVER HEATED SEAT (CC_SW_D_HSEATS) PID (PARAMETER IDENTIFICATION) OPERATION
  • Ignition OFF.
  • Disconnect: Driver Heated Seat Switch C2400.
  • Connect a fused jumper wire between:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C2400-1 C2400-4
  • The ignition is on.
  • Using the diagnostic scan tool, view the BCM parameter identification (PID) data.
  • Using the diagnostic scan tool, select the BCM. Observe the CC_SW_D_HSEATS PID state.
  • While observing the PID, remove the fused jumper wire.

Does the PID state change when the fuse jumper is removed?
Yes INSTALL a new driver heated seat switch.
No GO to B5
B5 CHECK THE DRIVER HEATED SEAT SWITCH SIGNAL CIRCUIT FOR OPEN OR SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280F.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2400-1 C2280F-8
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2400-1 Ground

Is the resistance between the heated seat switch and the BCM less than 5 ohms, and more than 10,000 ohms between the heated seat switch and ground?
Yes GO to B13
No REPAIR the circuit.
B6 CHECK THE RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: Driver Heated Seat Relay.
  • The ignition is on.
  • Action:
    Positive lead Measurement/Action Negative lead
    Driver Heated Seat Relay, Terminal 2. Ground

Is there voltage present?
Yes REPAIR the circuit.
No INSTALL a new driver heated seat relay. RECONNECT all connectors and REPEAT the self-test. If the DTC resets, GO to B13.
B7 CHECK THE RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: Driver Heated Seat Relay.
  • Disconnect: BCM C2280D.
  • Action:
    Positive lead Measurement/Action Negative lead
    Driver Heated Seat Relay, Terminal 2. Ground

Is the resistance greater than 10000 Ohms?
Yes GO to B8
No REPAIR the circuit.
B8 CHECK THE RELAY CONTROL CIRCUIT FOR AN OPEN
  • Action:
    Positive lead Measurement/Action Negative lead
    Driver Heated Seat Relay, Terminal 2. C2280D-5

Is the resistance less than 3 ohms?
Yes INSTALL a new driver heated seat relay. RECONNECT all connectors and REPEAT the self-test. If the DTC resets, GO to B13.
No REPAIR the circuit.
B9 CHECK THE DRIVER HEATED SEAT RELAY VOLTAGE
  • Ignition OFF.
  • Disconnect: Driver Heated Seat Relay.
  • The ignition is on.
  • Action:
    Positive lead Measurement/Action Negative lead
    Driver Heated Seat Relay, Terminal 1. Ground
    Driver Heated Seat Relay, Terminal 3. Ground

Is the voltage greater than 11 volts for both measurements?
Yes GO to B10
No REPAIR the circuit.
B10 CHECK THE HEATING MAT CIRCUIT VOLTAGE
  • Ignition OFF.
  • Connect: Driver Heated Seat Relay.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect the driver seat side airbag module C367.
  • Disconnect: Driver Seat Cushion Heater C364.
  • WARNING: Make sure no one is in the vehicle and nothing is blocking or positioned in front of any airbag while the battery is connected. Failure to follow these instructions may result in serious injury in the event of accidental deployment. Connect the battery ground cable.
    REFER TO: Battery Disconnection and Connection (414-01 Battery, Mounting and Cables, General Procedures).
  • Start the engine.
  • Activate the driver seat heater switch.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C364-1 Ground

Is the voltage greater than 11 volts?
Yes GO to B12
No GO to B11
B11 CHECK THE HEATER CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Driver seat heater relay.
  • Action:
    Positive lead Measurement/Action Negative lead
    Driver seat heater relay, socket pin 5. C364-1

Is the resistance less than 3 ohms?
Yes GO to B14
No REPAIR the circuit. CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test. CHECK the system for normal operation. DISCONNECT the battery ground cable. CONNECT the driver seat side airbag module C367. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
B12 CHECK THE SEAT HEATING MAT GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C364-2 Ground

Is the resistance less than 3 ohms?
Yes CHECK the connector and wiring for loose or damaged terminals. If OK, INSTALL a new driver seat cushion heating mat. CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test. CHECK the system for normal operation. DISCONNECT the battery ground cable. CONNECT the driver seat side airbag module C367. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
No REPAIR the circuit. CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test. CHECK the system for normal operation. DISCONNECT the battery ground cable. CONNECT the driver seat side airbag module C367. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
B13 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Ignition OFF.
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
B14 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Ignition OFF.
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSB applies to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
DISCONNECT the battery ground cable. CONNECT the driver seat side airbag module C367. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal problems. DISCONNECT the battery ground cable. CONNECT the driver seat side airbag module C367. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).

Seat Heater Inoperative/Operates Incorrectly - Passenger


Refer to Wiring Diagrams Cell 119 for schematic and connector information.

Normal Operation and Fault Symptoms

The heated seat system operates only with the engine running. When the driver or passenger heated seat switch (located in the instrument panel) is activated, it supplies a ground signal to the BCM. When the BCM receives the heated seat switch signal, it activates the corresponding (driver or passenger) heated seat relay (located in the CJB). When the heated seat relay is energized, voltage is supplied to the seat heating mats. The heating mats are directly connected to ground, completing the heated seat electrical circuit.


DTC Fault Trigger Conditions


Trouble Code Description Fault Trigger Conditions
B1036:12 Front Right Seat Heater Element: Short to Battery If the passenger seat heater relay control circuit is shorted to voltage and the BCM attempts to activate the passenger seat heater relay, this DTC is set and the seat does not heat.
B1036:14 Right Front Seat Heater Element: Short to Ground or Open Circuit If the passenger seat heater relay control circuit is open or shorted to ground and the BCM attempts to activate the passenger seat heater relay, this DTC is set and the seat does not heat (open circuit) or may not heat at all (short to ground) until the ignition is turned off.
B115A: 23 Front Passenger Seat Heater: Low Signal Level Sets when the BCM detects that the passenger seat heater switch is active during an on-demand self-test or has been active for more than 2 minutes.

Possible Sources

  • Heated Seat Relay
  • Heated Seat Switch
  • Wiring, Terminals or Connectors
  • Heater Pad
  • BCM

DIAGNOSTIC TEST C: SEAT HEATER INOPERATIVE/INCORRECT OPERATION - PASSENGER
C1 RETRIEVE BCM (BODY CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
  • The ignition is on.
  • Using a scan tool, perform the BCM self-test.

Is DTC B1034:12, B1034:14 or B115B:23 present?
Yes If DTC B1036:14 is present, GO to C7.
If DTC B1036:12 is present, GO to C6.
If DTC B115A:23 is present, GO to C4.
For information on all other diagnostic trouble codes (DTCs), REFER TO the BCM DTC Chart.
No If the seat cushion and seat back heating mats do not operate, GO to C2.
If only the seat cushion heating mat does not operate, INSTALL a new passenger seat cushion heating mat.
If only the seat back heating mat does not operate, INSTALL a new passenger seat back heating mat.
C2 CHECK THE PASSENGER SEAT HEATER (CC_SW_P_HSEATS) PID (PARAMETER IDENTIFICATION) OPERATION
  • Ignition OFF.
  • Using a diagnostic scan tool, monitor the BCM CC_SW_P_HSEATS PID while pressing and releasing the passenger seat heater switch.

Does the PID match the passenger heater switch status?
Yes GO TO C9
No GO to C3
C3 CHECK THE PASSENGER SEAT HEATER SWITCH GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect: passenger seat heater/ambient lighting switch C2401.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2401-4 Ground

Is the resistance less than 3 ohms?
Yes GO TO C4
No REPAIR the circuit.
C4 CHECK THE BCM (BODY CONTROL MODULE) PASSENGER SEAT HEATER (CC_SW_D_HSEATS) PID (PARAMETER IDENTIFICATION) OPERATION
  • Ignition OFF.
  • Disconnect: passenger seat heater/ambient lighting switch C2401.
  • Connect a fused jumper wire between:
    Click to display connectors
    Positive lead Measurement/Action Negative lead
    C2401-4 C2401-6
  • The ignition is on.
  • Using the diagnostic scan tool, view the BCM parameter identification (PID) data.
  • Using a diagnostic scan tool, select the BCM. Check the status of the CC_SW_P_HSEATS PID.
  • While observing the PID, remove the fused jumper wire.

Does the PID state change when the fuse jumper is removed?
Yes INSTALL a new passenger seat heater/ambient lighting switch.
No GO to C5
C5 CHECK THE PASSENGER HEATER SWITCH SIGNAL CIRCUIT FOR AN OPEN OR SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280F.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2401-6 C2280F-6
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2401-6 Ground

Is the resistance between the heated seat switch and the BCM less than 5 ohms, and more than 10,000 ohms between the heated seat switch and ground?
Yes GO TO C13
No REPAIR the circuit.
C6 CHECK THE RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: passenger seat heater relay.
  • The ignition is on.
  • Action:
    Positive lead Measurement/Action Negative lead
    Passenger seat heater relay, socket pin 2. Ground

Is there voltage present?
Yes REPAIR the circuit.
No INSTALL a new passenger seat heater relay. RECONNECT all connectors and REPEAT the self-test. If the DTC resets, GO to C13.
C7 CHECK THE RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: passenger seat heater relay.
  • Disconnect: BCM C2280D.
  • Action:
    Positive lead Measurement/Action Negative lead
    Passenger seat heater relay, socket pin 2. Ground

Is the resistance greater than 10000 Ohms?
Yes GO TO C8
No REPAIR the circuit.
C8 CHECK THE RELAY CONTROL CIRCUIT FOR AN OPEN
  • Action:
    Positive lead Measurement/Action Negative lead
    Passenger seat heater relay, socket pin 2. C2280D-16

Is the resistance less than 3 ohms?
Yes INSTALL a new passenger seat heater relay. RECONNECT all connectors and REPEAT the self-test. If the DTC is logged again, GO to C13.
No REPAIR the circuit.
C9 CHECK THE VOLTAGE AT THE PASSENGER SEAT HEATER RELAY
  • Ignition OFF.
  • Disconnect: passenger seat heater relay.
  • The ignition is on.
  • Action:
    Positive lead Measurement/Action Negative lead
    Passenger seat heater relay, terminal 1. Ground
    Passenger seat heater relay, terminal 3. Ground

Is the voltage greater than 11 volts for both measurements?
Yes GO TO C10
No REPAIR the circuit.
C10 CHECK THE VOLTAGE IN THE HEATING ELEMENT CIRCUIT
  • Ignition OFF.
  • Connect: passenger seat heater relay.
  • De-power the SRS.
    REFER to: Supplemental Restraint System (SRS) Disabling and Re-enabling (501-20B Supplemental Restraint System, General Procedures).
  • Disconnect the passenger side airbag module C337.
  • Disconnect: passenger seat cushion heater C334.
  • WARNING: Make sure no one is in the vehicle and nothing is blocking or positioned in front of any airbag while the battery is connected. Failure to follow these instructions may result in serious injury in the event of accidental deployment. Connect the battery ground cable.
    REFER TO: Battery Disconnection and Connection (414-01 Battery, Mounting and Cables, General Procedures).
  • Start the engine.
  • Activate the passenger seat heater switch.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C334-1 Ground

Is the voltage greater than 11 volts?
Yes GO TO C12
No GO TO C11
C11 CHECK THE HEATER CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Passenger seat heater relay.
  • Action:
    Positive lead Measurement/Action Negative lead
    Passenger seat heater relay, terminal 5. C334-1

Is the resistance less than 3 ohms?
Yes GO TO C14
No REPAIR the circuit. CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test. CHECK the system for normal operation. DISCONNECT the battery ground cable. CONNECT the passenger seat airbag module C337. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disarming and Re-arming (501-20B Supplemental Restraint System, General Procedures).
C12 CHECK THE HEATING ELEMENT GROUND CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C334-2 Ground

Is the resistance less than 3 ohms?
Yes CHECK the connector and wiring for loose or damaged terminals. If OK, INSTALL a new passenger seat cushion heating element. CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test. CHECK the system for normal operation. DISCONNECT the battery ground cable. CONNECT the passenger side airbag module C337. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disarming and Re-arming (501-20B Supplemental Restraint System, General Procedures).
No REPAIR the circuit. CLEAR the Diagnostic Trouble Codes (DTCs). REPEAT the self-test. CHECK the system for normal operation. DISCONNECT the battery ground cable. CONNECT the passenger seat airbag module C337. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disarming and Re-arming (501-20B Supplemental Restraint System, General Procedures).
C13 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Ignition OFF.
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.
C14 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Ignition OFF.
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSB applies to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
DISCONNECT the battery ground cable. CONNECT the passenger side airbag module C337. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disarming and Re-arming (501-20B Supplemental Restraint System, General Procedures).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal problems. DISCONNECT the battery ground cable. CONNECT the passenger side airbag module C337. REPEAT the SRS.
REFER TO: Supplemental Restraint System (SRS) Disarming and Re-arming (501-20B Supplemental Restraint System, General Procedures).

Seat heater operates incorrectly - driver or passenger seat heats when the system is off


Refer to Wiring Diagrams Cell 119 for schematic and connector information.

Normal Operation and Fault Symptoms

The seat heater system operates only with the engine running. When the driver or passenger seat heater switch (located in the instrument panel) is activated, it supplies a ground signal to the BCM. When the BCM receives the seat heater switch signal, it activates the corresponding (driver or passenger) seat heater relay (located in the CJB). When the seat heater relay is energized, voltage is supplied to the seat cushion heater mat. The seat cushion heater mats are directly connected to ground to complete the seat heater electrical circuit.


DTC Fault Trigger Conditions


Trouble Code Description Fault Trigger Conditions
B1034:14 Left Front Seat Heater Element: Short to Ground or Open Circuit If the driver heated seat relay control circuit is open or shorted to ground and the BCM attempts to activate the driver heated seat relay, this DTC sets and the seat does not heat (open circuit) or may heat only once (short to ground) until the ignition is turned off.
B1036:14 Right Front Seat Heater Element: Short to Ground or Open Circuit If the passenger seat heater relay control circuit is open or shorted to ground, and the BCM attempts to activate the passenger seat heater relay, this DTC is set and the seat does not heat (open circuit) or may heat continuously until the ignition is turned off (short to ground).

Possible Sources

  • Heated Seat Relay
  • Wiring, Terminals or Connectors
  • BCM

DIAGNOSTIC TEST D: SEAT HEATER INOPERATIVE CORRECTLY - DRIVER OR PASSENGER SEAT HEATS WHEN SYSTEM IS OFF
D1 CHECK THE RELAY OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: driver or passenger seat heater relay.
  • The ignition is on.
  • For the driver heated seat, measure:
    Positive lead Measurement/Action Negative lead
    Driver seat heater relay, socket pin 5. Ground
  • For the passenger heated seat, measure:
    Positive lead Measurement/Action Negative lead
    Passenger seat heater relay, terminal 5. Ground

Is there voltage present?
Yes REPAIR the circuit.
No GO to D2
D2 CHECK THE RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280D.
  • The ignition is on.
  • For the driver heated seat, measure:
    Positive lead Measurement/Action Negative lead
    Driver Heated Seat Relay, Terminal 2. Ground
  • For the passenger heated seat, measure:
    Positive lead Measurement/Action Negative lead
    Passenger seat heater relay, socket pin 2. Ground

Is the resistance greater than 10000 Ohms?
Yes INSTALL a new driver or passenger seat heater relay. CONNECT all connectors. CHECK the system for normal operation. If the concern persists, GO to D3.
No REPAIR the circuit.
D3 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Ignition OFF.
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.

Seat heater operates incorrectly - driver seat heats but the seat heater indicator does not illuminate when pressed


Refer to Wiring Diagrams Cell 119 for schematic and connector information.

Normal Operation and Fault Symptoms

The seat heater system operates only with the engine running. When the driver or passenger seat heater switch (located in the instrument panel) is activated, it supplies a ground signal to the BCM. When the BCM receives the seat heater switch signal, it activates the corresponding (driver or passenger) seat heater relay (located in the CJB). When the seat heater relay is energized, the BCM supplies voltage to illuminate the seat heater on indicator.

Possible Sources

  • Wiring, Terminals or Connectors
  • Heated Seat Switch
  • BCM

DIAGNOSTIC TEST E: SEAT HEATER OPERATING INCORRECTLY - DRIVER SEAT HEATS BUT SEAT HEATER INDICATOR DOES NOT ILLUMINATE WHEN PRESSED
E1 CHECK THE INDICATOR CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280E.
  • Disconnect: Driver Heated Seat Switch C2400.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2400-2 Ground

Is the resistance greater than 10000 Ohms?
Yes GO to E2
No REPAIR the circuit.
E2 CHECK THE INDICATOR CIRCUIT FOR AN OPEN
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2400-2 C2280E-15

Is the resistance less than 3 ohms?
Yes GO to E3
No REPAIR the circuit.
E3 CHECK THE INDICATOR OPERATION
  • Connect: driver seat heater switch C2400.
  • While observing the seat heater switch indicator, momentarily connect a fused jumper wire between:
    Positive lead Measurement/Action Negative lead
    Battery positive C2280E-15

Did the seat heater switch indicator illuminate when the fused jumper wire was connected?
Yes GO to E4
No INSTALL a new driver heated seat switch.
E4 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.

Seat heater operates incorrectly - passenger seat heats but the seat heater indicator does not illuminate when pressed


Refer to Wiring Diagrams Cell 119 for schematic and connector information.

Normal Operation and Fault Symptoms

The seat heater system operates only with the engine running. When the driver or passenger seat heater switch (located in the instrument panel) is activated, it supplies a ground signal to the BCM. When the BCM receives the seat heater switch signal, it activates the corresponding (driver or passenger) seat heater relay (located in the CJB). When the seat heater relay is energized, the BCM supplies voltage to illuminate the seat heater on indicator.

Possible Sources

  • Wiring, Terminals or Connectors
  • Heated Seat Switch
  • BCM

DIAGNOSTIC TEST F: SEAT HEATER OPERATING INCORRECTLY - PASSENGER SEAT HEATS BUT SEAT HEATER INDICATOR DOES NOT ILLUMINATE WHEN PRESSED
F1 CHECK THE INDICATOR CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect: BCM C2280E.
  • Disconnect: passenger seat heater/ambient lighting switch C2401.
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2401-3 Ground

Is the resistance greater than 10000 Ohms?
Yes GO to F2
No REPAIR the circuit.
F2 CHECK THE INDICATOR CIRCUIT FOR AN OPEN
  • Action:
    Click to display the connectors
    Positive lead Measurement/Action Negative lead
    C2401-3 C2280E-3

Is the resistance less than 3 ohms?
Yes GO to F3
No REPAIR the circuit.
F3 CHECK THE INDICATOR OPERATION
  • Connect: Passenger/Ambient Lighting Seat Heater Switch C2401.
  • While observing the seat heater switch indicator, momentarily connect a fused jumper wire between:
    Positive lead Measurement/Action Negative lead
    Battery positive C2280E-3

Did the seat heater switch indicator illuminate when the fused jumper wire was connected?
Yes GO to F4
No INSTALL a new passenger seat heater/ambient lighting switch.
F4 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.

Seat heater operates incorrectly - driver or passenger seat heater indicator stays on


Refer to Wiring Diagrams Cell 119 for schematic and connector information.

Normal Operation and Fault Symptoms

The seat heater system operates only with the engine running. When the driver or passenger seat heater switch (located in the instrument panel) is activated, it supplies a ground signal to the BCM. When the BCM receives the seat heater switch signal, it activates the corresponding (driver or passenger) seat heater relay (located in the CJB). When the seat heater relay is energized, the BCM supplies voltage to illuminate the seat heater on indicator.

Possible Sources

  • Wiring, Terminals or Connectors
  • BCM

DIAGNOSTIC TEST G: SEAT HEATER INOPERATIVE CORRECTLY - DRIVER OR PASSENGER SEAT HEATER INDICATOR IS ALWAYS ON
G1 CHECK THE INDICATOR CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect: BCM C2280E.
  • The ignition is on.
  • Observe the corresponding seat heater switch.

Does the corresponding seat heater switch indicator light come on?
Yes REPAIR the seat heater switch indicator circuit for a short to the power supply voltage.
No GO to G2
G2 CHECK THE BCM (BODY CONTROL MODULE) FOR PROPER OPERATION
  • Ignition OFF.
  • Disconnect all BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals - clean module pins)
    • damaged or bent pins - if necessary, install new terminals/pins
    • pushed-out pins - install new pins as necessary
  • Reconnect the BCM and all previously disconnected system connectors. Make sure they are fully seated and locked.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable technical service bulletins (TSBs). If a TSB exists for this concern, STOP this test and FOLLOW the TSB instructions. If no TSBs apply to this concern, INSTALL a new BCM.
REFER TO: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Removal and Installation).
No The system is currently operating correctly. The concern may have been caused by module connections. ADDRESS the root cause of any connector or terminal issues.

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