Toyota 4Runner: ECM Communication Circuit Malfunction (C1203)

Toyota 4Runner Service Manual / Brake / Brake Control / Dynamic Control Systems / Vehicle Stability Control System(for Hydraulic Brake Booster) / ECM Communication Circuit Malfunction (C1203)

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

REPLACE ECM

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

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