C1553

POWER STEERING: POWER STEERING SYSTEM: C1552/52-C1555/55: PIG Power Source Circuit
C1555/55 - EPS Motor Relay Circuit

DESCRIPTION

When a problem occurs in the system, the power source relay circuit and the motor relay circuit are shut off to stop the power assist. The ECU must be replaced when there is a problem with the relays because each relay is built into the ECU.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (PIG POWER SUPPLY)

(a) Connect a 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) Select the item "PIG Power Supply" in the Data List and read the value displayed on the Techstream.

EMPS:





OK:

The normal condition value is displayed on the Techstream.

NG -- INSPECT FUSE (EPS FUSE)

OK -- CHECK FOR INTERMITTENT PROBLEMS How to Proceed With Troubleshooting

2. INSPECT FUSE (EPS FUSE)

(a) Remove the EPS fuse from the engine room relay block.





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

Standard resistance:





NG -- CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE
OK -- Continue to next step.

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

(a) Disconnect the connector 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:





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

4. INSPECT STEERING COLUMN ASSEMBLY (POWER STEERING MOTOR)

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





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

Standard resistance:





NG -- REPLACE STEERING COLUMN ASSEMBLY Removal

OK -- REPLACE POWER STEERING ECU Removal