Diesel Data: Automotive Repair

EPS Warning Light Circuit








POWER ASSIST SYSTEMS: POWER STEERING SYSTEM (for 2AZ-FE): EPS Warning Light Circuit

EPS Warning Light Circuit

DESCRIPTION

If the power steering ECU detects a malfunction, the P/S warning light comes on. At this time, the power steering ECU stores a DTC in its memory.

WIRING DIAGRAM









INSPECTION PROCEDURE
NOTE: If the steering column assembly or power steering ECU has been replaced, perform the rotation angle sensor initialization and torque sensor zero point calibration Programming and Relearning.

PROCEDURE

1. CHECK FOR DTC (CAN COMMUNICATION SYSTEM)
(a) Check for DTCs.
OK:
DTC is not output.
NG -- GO TO CAN COMMUNICATION SYSTEM
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (POWER STEERING ECU - BODY GROUND)
(a) Disconnect the connectors from the power steering ECU.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:





(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:






B -- REPAIR OR REPLACE HARNESS OR CONNECTOR
A -- Continue to next step.
3. REPLACE POWER STEERING ECU
(a) Replace the power steering ECU Removal.
(b) Check the P/S warning light condition.
OK:
P/S warning light operates normally.
NG -- GO TO COMBINATION METER SYSTEM
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE