C1437

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: 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.





INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform calibration 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





OK:

Normal (there are no momentary interruptions).

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

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

2. RECONFIRM DTC

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

(b) Turn the ignition switch off.

(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 Reading and Clearing Diagnostic Trouble Codes.

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

Result





C -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) How To Proceed With Troubleshooting

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

(a) Turn the ignition 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.

NEXT -- Continue to next step.

4. RECONFIRM DTC

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

(b) Turn the ignition switch off.

(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 Reading and Clearing Diagnostic Trouble Codes.

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

Result





C -- GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) How to Proceed With Troubleshooting

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- END