EPS Warning Light Circuit

POWER ASSIST SYSTEMS: POWER STEERING SYSTEM: EPS Warning Light Circuit
- EPS Warning Light Circuit

DESCRIPTION

The power steering ECU is connected to the combination meter via CAN communication. If the power steering ECU detects a malfunction, the EPS warning light comes on. At this time, vehicle enters a fail-safe mode.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. INSPECT CAN COMMUNICATION SYSTEM

(a) Check if the CAN communication system DTC is output Diagnosis System.

Result





B -- GO TO CAN COMMUNICATION SYSTEM Initial Inspection and Diagnostic Overview
A -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (POWER STEERING ECU - BATTERY)

(a) Disconnect the power steering ECU connector.





(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





NG -- INSPECT IG POWER SOURCE CIRCUIT IG Power Source Circuit
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (POWER STEERING ECU - BODY GROUND)

(a) Measure the resistance according to the value(s) in the table below.





Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

4. CHECK EPS WARNING LIGHT USING TECHSTREAM (COMBINATION METER)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON and the Techstream on.

(c) Perform the Active Test of the combination meter (meter CPU) using the Techstream Meter / Gauge System.

Combination Meter





(d) Check that the EPS warning light turns on and off in the combination meter using the Techstream.

OK:

The EPS warning light turns on and off in accordance with the Techstream operation.

NG -- INSPECT COMBINATION METER How To Proceed With Troubleshooting

OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Power Steering System