Toyota 4Runner Quiz
Brake

ECM Communication Circuit Malfunction (C1203)

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DESCRIPTION

The circuit is used to send control information from the skid control ECU to the ECM, and engine control information from the ECM to the skid control ECU via the CAN communication system.

DTC Code

DTC Detection Condition

Trouble Area

C1203

The engine/drivetrain specification and/or destination information from the ECM does not match the skid control ECU data.

ECM
PROCEDURE

  1. CHECK DTC (ENGINE CONTROL SYSTEM)

(a) Check if any DTC is recorded for the engine control system (See page ).


Result

Result

Proceed to

DTC is not output

A

DTC is output

B

A

REPLACE ECM

B

GO TO ENGINE CONTROL SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

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