Toyota 4Runner Quiz
Power Source / Network

Open in CAN Main Wire

In this manual: Power Source / Network
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~7min read
DESCRIPTION

There may be an open circuit in the CAN main wire and/or DLC3 branch wire when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 69 Ω or higher.

Symptom

Trouble Area

The resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 69 Ω or higher.
  • CAN main wire and connector
  • No. 1 junction connector*
  • No. 2 junction connector
  • No. 3 junction connector
  • No. 4 junction connector
  • ECM
  • Combination meter assembly
  • DLC3 branch wire or connector

*: for 4WD

WIRING DIAGRAM
CAUTION / NOTICE / HINT

HINT:

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE

  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL

(a) Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and branch wire.

CAUTION:

Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

NOTICE:

When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See page ).


NEXT

  1. CHECK FOR OPEN IN CAN BUS WIRE (NO. 2 JUNCTION CONNECTOR - DLC3)

(a) Disconnect the F59 No. 2 junction connector connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F59-4 (CANH) - F13-6 (CANH)

Ignition switch off

Below 1 Ω

F59-15 (CANL) - F13-14 (CANL)

Ignition switch off

Below 1 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 2 Junction Connector)

*b

Front view of DLC3

NG

REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CANH, CANL)
OK

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 2 JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F59-3 (CANH) - F59-14 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 2 Junction Connector)
Result

Result

Proceed to

OK

A

NG (for 2WD)

B

NG (for 4WD)

C

B

GO TO STEP 5

C

GO TO STEP 7
A

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 2 JUNCTION CONNECTOR - ECM)

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F59-1 (CANH) - F59-12 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 2 Junction Connector)

OK

REPAIR OR REPLACE NO. 2 JUNCTION CONNECTOR

NG

GO TO STEP 12

  1. CONNECT CONNECTOR

(a) Reconnect the F59 No. 2 junction connector connector.

NEXT

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (COMBINATION METER ASSEMBLY - NO. 2 JUNCTION CONNECTOR)

(a) Disconnect the F14 combination meter assembly connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F14-1 (CANH) - F14-2 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Front view of wire harness connector

(to Combination Meter Assembly)

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO COMBINATION METER ASSEMBLY (COMBINATION METER ASSEMBLY - NO. 2 JUNCTION CONNECTOR)

  1. CONNECT CONNECTOR

(a) Reconnect the F59 No. 2 junction connector connector.

NEXT

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 1 JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)

(a) Disconnect the A36 No. 1 junction connector connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

A36-3 (CANH) - A36-6 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 1 Junction Connector)

NG

GO TO STEP 10
OK

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 1 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

A36-2 (CANH) - A36-5 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 1 Junction Connector)

OK

REPAIR OR REPLACE NO. 1 JUNCTION CONNECTOR

NG

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 1 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)

  1. CONNECT CONNECTOR

(a) Reconnect the A36 No. 1 junction connector connector.

NEXT

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (COMBINATION METER ASSEMBLY - NO. 1 JUNCTION CONNECTOR)

(a) Disconnect the F14 combination meter assembly connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F14-1 (CANH) - F14-2 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Front view of wire harness connector

(to Combination Meter Assembly)

OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO COMBINATION METER ASSEMBLY (COMBINATION METER ASSEMBLY - NO. 1 JUNCTION CONNECTOR)

  1. CONNECT CONNECTOR

(a) Reconnect the F59 No. 2 junction connector connector.

NEXT

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 4 JUNCTION CONNECTOR - ECM)

(a) Disconnect the G13 No. 4 junction connector connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

G13-5 (CANH) - G13-16 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 4 Junction Connector)

NG

GO TO STEP 15
OK

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 4 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

G13-6 (CANH) - G13-17 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 4 Junction Connector)

OK

REPAIR OR REPLACE NO. 4 JUNCTION CONNECTOR

NG

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 4 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)

  1. CONNECT CONNECTOR

(a) Reconnect the G13 No. 4 junction connector connector.

NEXT

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 3 JUNCTION CONNECTOR - ECM)

(a) Disconnect the F60 No. 3 junction connector connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F60-2 (CANH) - F60-13 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 3 Junction Connector)

NG

GO TO STEP 18
OK

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 3 JUNCTION CONNECTOR - NO. 4 JUNCTION CONNECTOR)

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F60-1 (CANH) - F60-12 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to No. 3 Junction Connector)

OK

REPAIR OR REPLACE NO. 3 JUNCTION CONNECTOR

NG

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 3 JUNCTION CONNECTOR - NO. 4 JUNCTION CONNECTOR)

  1. CONNECT CONNECTOR

(a) Reconnect the F60 No. 3 junction connector connector.

NEXT

  1. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - NO. 3 JUNCTION CONNECTOR)

(a) Disconnect the F50 ECM connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

F50-32 (CANH) - F50-31 (CANL)

Ignition switch off

108 to 132 Ω
Text in Illustration

*a

Rear view of wire harness connector

(to ECM)

OK

REPLACE ECM

NG

REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (ECM - NO. 3 JUNCTION CONNECTOR)

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