Lost Communication with Rear Gate Module (U0230)

DESCRIPTION

DTC No.	DTC Detection Condition	Trouble Area
U0230	No communication from the power back door ECU (back door motor unit) or back door closer ECU continues.	Power back door ECU (back door motor unit) or back door closer ECU branch wire or connector Power source circuit of power back door ECU (back door motor unit) or back door closer ECU Power back door ECU (back door motor unit) or back door closer ECU

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

• Turn the ignition switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
• Turn the ignition switch off before inspecting CAN bus wires for a ground short.
• After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.
• Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

HINT:

• Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
• Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE

1. RECONFIRM DTC OUTPUT

(a) Reconfirm DTCs.

HINT:

If CAN MS bus DTC U1002 is output from the main body ECU (Techstream display: Main Body), troubleshoot for U1002 and check for malfunctions in the CAN MS bus circuit.

Result	Proceed to
U1002 is not output from main body ECU (Techstream display: Main Body)	A
U1002 is output from main body ECU (Techstream display: Main Body)	B

B

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

A

1. CHECK VEHICLE TYPE

(a) Check vehicle type.

Result

Result	Proceed to
w/ Power back door system	A
w/ Back door closer system	B

B

GO TO STEP 6

A

1. CHECK FOR OPEN IN CAN BUS WIRES (POWER BACK DOOR ECU (BACK DOOR MOTOR UNIT) BRANCH WIRE)

(a) Turn the ignition switch off.

(b) Disconnect the power back door ECU (back door motor unit) connector. Text in Illustration *1 Front view of wire harness connector (to Power Back Door ECU (Back Door Motor Unit))

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
L20-6 (MPX1) - L20-5 (MPX2)	Ignition switch off	54 to 69 Ω

NG

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (POWER BACK DOOR ECU (BACK DOOR MOTOR UNIT) BRANCH WIRE)

OK

1. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

(a) Measure the voltage according to the value(s) in the table below. Standard Voltage: Tester Connection Condition Specified Condition L20-10 (ECUB) - Body ground Always 11 to 14 V L20-8 (IG) - Body ground Ignition switch ON 11 to 14 V Text in Illustration *1 Front view of wire harness connector (to Power Back Door ECU (Back Door Motor Unit))

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

OK

1. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)

(a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition L20-11 (GND) - Body ground Always Below 1 Ω Text in Illustration *1 Front view of wire harness connector (to Power Back Door ECU (Back Door Motor Unit))

OK

REPLACE POWER BACK DOOR ECU (POWER BACK DOOR UNIT ASSEMBLY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)

1. CHECK FOR OPEN IN CAN BUS WIRES (BACK DOOR CLOSER ECU BRANCH WIRE)

(a) Turn the ignition switch off.

(b) Disconnect the back door closer ECU connector. Text in Illustration *1 Front view of wire harness connector (to Back Door Closer ECU)

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
L21-12 (MPX2) - L21-11 (MPX1)	Ignition switch off	54 to 69 Ω

NG

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (BACK DOOR CLOSER ECU BRANCH WIRE)

OK

1. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

(a) Measure the voltage according to the value(s) in the table below. Standard Voltage: Tester Connection Condition Specified Condition L21-16 (ECUB) - Body ground Always 11 to 14 V L21-15 (IG) - Body ground Ignition switch ON 11 to 14 V Text in Illustration *1 Front view of wire harness connector (to Back Door Closer ECU)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

OK

1. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)

(a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition L21-3 (GND) - Body ground Always Below 1 Ω Text in Illustration *1 Front view of wire harness connector (to Back Door Closer ECU)

OK

REPLACE BACK DOOR CLOSER ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)