C1437

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

DTC C1437 - Lost Communication with ECM

DESCRIPTION

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






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)
(a) Using Techstream, check for any momentary interruption in the wire harness and connector corresponding to the DTC Check for Intermittent Problems.

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 ignition 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
B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION)
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.
(d) Check that there is no momentary interruption.
NEXT -- Continue to next step.
4. RECONFIRM DTC
(a) Turn the ignition 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
B -- REPLACE BRAKE ACTUATOR ASSEMBLY
A -- END