PS Warning Light Remains ON

POWER ASSIST SYSTEMS: POWER STEERING SYSTEM: PS Warning Light Remains ON
- PS Warning Light Remains ON

DESCRIPTION

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

Also if the battery is not sufficiently charged or the voltage decreases temporarily, the amount of power assist may be reduced and the EPS warning light may come on.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:
* When the steering column assembly is replaced, perform the assist map writing Programming and Relearning.
* Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. CHECK DTC OUTPUT

(a) Check for DTCs for power steering system Reading and Clearing Diagnostic Trouble Codes.

Result

B -- GO TO DTC CHART Power Steering System
A -- Continue to next step.

2. READ VALUE USING TECHSTREAM (BATTERY VOLTAGE LO RECORD)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Chassis / EMPS / Data List.

(e) In accordance with the display on the Techstream, read the Data List.

EMPS

OK:

"Battery Voltage Lo Record" is 0 times.

Result

C -- GO TO CHARGING SYSTEM Problem Symptoms Table

B -- GO TO CHARGING SYSTEM Problem Symptoms Table
A -- Continue to next step.

3. CHECK CAN COMMUNICATION SYSTEM

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

Result

B -- GO TO CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting
A -- Continue to next step.

4. PERFORM ACTIVE TEST USING TECHSTREAM (INDICATE EPS)

(a) Connect the Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Combination Meter / Active Test.

(e) Check that the EPS warning light operates in accordance with the Active Test.

Combination Meter

OK:

The EPS warning light operation normally.

NG -- GO TO METER / GAUGE SYSTEM Removal
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (STEERING COLUMN ASSEMBLY - BATTERY AND BODY GROUND)

(a) Disconnect the connector from the steering column assembly (power steering ECU).

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

Standard Voltage:

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

6. CHECK HARNESS AND CONNECTOR (STEERING COLUMN ASSEMBLY - IG POWER SUPPLY)

(a) Turn the ignition switch to ON.

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

Standard Voltage:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE STEERING COLUMN ASSEMBLY Removal