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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 U Code Charts.

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 .

(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 .

(f) Check if the same DTC is recorded .

Result:





C -- INSPECT CAN COMMUNICATION SYSTEM

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Diagnosis System

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 .

(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 .

(f) Check if the same DTC is recorded .

Result:





C -- INSPECT CAN COMMUNICATION SYSTEM

B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal

A -- END