Toyota Tacoma (2015-2018) Service Manual: ECM Communication Circuit Malfunction (C1203)

Toyota Tacoma (2015-2018) Service Manual / Brake Control / Dynamic Control Systems / Vehicle Stability Control System(for Hydraulic Brake Booster) / ECM Communication Circuit Malfunction (C1203)

DESCRIPTION

The circuit sends TRAC, A-TRAC and VSC control information from the skid control ECU (master cylinder solenoid) to the ECM, and engine control information from the ECM to the skid control ECU (master cylinder solenoid) via the CAN communication system.

DTC Code	DTC Detection Condition	Trouble Area
C1203	Information relating to engine drive source or destination stored in ECM does not match that stored in skid control ECU (master cylinder solenoid).	CAN communication system ECM

PROCEDURE

1.	CHECK CAN COMMUNICATION SYSTEM

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Select CAN Bus Check from the System Selection Menu screen and follow the prompts on the screen to inspect the CAN bus (See page OK: OK: ).

OK:

CAN Bus Check indicates no malfunctions in CAN communication.

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

2.	CHECK DTC (SFI SYSTEM)

(a) Check if any DTC is recorded for the SFI system (See page Result ).

Result

Result	Proceed to
DTC is output	A
DTC is not output	B

GO TO SFI SYSTEM

REPLACE ECM

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