Power Steering System

POWER STEERING: POWER STEERING SYSTEM: C1581/81: Assist Map Un-Writing
C1581/81 - Assist Map Un-Writing

DESCRIPTION

The power steering ECU outputs this DTC when it determines that the assist map is not written in the ECU.

The power steering ECU must be replaced when this DTC is output because this malfunction cannot be repaired.

HINT
The assist map data is written in the power steering ECU to control assisting power. The assist map is selected from five types based on the vehicle specification communication data (designation and grade package information).





INSPECTION PROCEDURE

NOTICE:
If replacing the power steering ECU, initialize and calibrate the torque sensor zero point Programming and Relearning.

PROCEDURE

1. PERFORM ASSIST MAP WRITING

(a) Connect a Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream on.

(d) Set the Techstream to Test Mode (select "Signal Check").

HINT
Refer to the Techstream operator's manual for further details.

(e) Wait for 5 seconds or more.

HINT
Assist map is automatically written when approximately 5 seconds have elapsed after setting the Techstream to Test Mode. DTC C1581/81 will be cleared after the assist map is written.

(f) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.

OK:

DTC C1581/81 is not output.

NG -- CHECK CAN COMMUNICATION SYSTEM

OK -- END

2. CHECK CAN COMMUNICATION SYSTEM

(a) Check for DTCs of the CAN communication system Diagnosis System.

OK:

DTCs are not output.

NG -- GO TO CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting
OK -- Continue to next step.

3. CHECK ECM

(a) Check if a qualified ECM is installed.

OK:

A qualified ECM is installed.

NG -- REPLACE ECM

OK -- REPLACE POWER STEERING ECU