Operation CHARM: Car repair manuals for everyone.

C1437





BRAKE CONTROL: VEHICLE STABILITY CONTROL SYSTEM: C1437: Lost Communication with ECM
C1437 - Lost Communication with ECM

DESCRIPTION

The skid control ECU receives signals from the ECM via the CAN communication system.





WIRING DIAGRAM

Refer to DTCs U0073, U0100, U0123, U0124 and U0126 U0073.

INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration and store system information Programming and Relearning.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

(a) Using the Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC Check For Intermittent Problems.

ABS/VSC/TRAC

ABS/VSC/TRAC:





OK:

There are no momentary interruptions.

HINT
Perform the above inspection before removing the sensor and connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - ECM)
OK -- Continue to next step.

2. RECONFIRM DTC

(a) Turn the engine switch off.

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(c) Start the engine.

(d) Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.

(e) Check that no CAN communication system DTC is output Diagnosis System.

(f) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.

Result:





C -- INSPECT CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- CHECK FOR INTERMITTENT PROBLEMS Electronic Circuit Inspection Procedure

3. REPAIR OR REPLACE HARNESS OR CONNECTOR (SKID CONTROL ECU - ECM)

(a) Turn the engine switch off.

(b) Repair or replace the harness or connector.

(c) Check for any momentary interruption between the skid control ECU and the ECM Check For Intermittent Problems.

(d) Check that there is no momentary interruption.

NEXT -- Continue to next step.

4. RECONFIRM DTC

(a) Turn the engine switch off.

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(c) Start the engine.

(d) Drive the vehicle at a speed of 15 km/h (9 mph) or more for 10 seconds or more.

(e) Check that no CAN communication system DTC is output Diagnosis System.

(f) Check if the same DTC is recorded Reading and Clearing Diagnostic Trouble Codes.

Result:





C -- INSPECT CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- END