C1531

POWER ASSIST SYSTEMS: POWER STEERING SYSTEM: C1531: ECU Malfunction
C1531 - ECU Malfunction

DESCRIPTION

This circuit supplies electric power to the power steering solenoid valve.

The power steering ECU controls the output current to the power steering solenoid valve in accordance with the steering angle signal, steering zero point memory, vehicle speed signal and engine speed signal, adjusting the amount of power steering assist.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING TECHSTREAM (SOLENOID CURRENT)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / PPS / Data List.

PPS





OK:

The normal condition value is displayed the Techstream.

NG -- CHECK HARNESS AND CONNECTOR (POWER STEERING ECU - POWER STEERING SOLENOID VALVE)

OK -- REPLACE POWER STEERING ECU ASSEMBLY Removal

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

(a) Disconnect the power steering ECU and power steering solenoid valve connectors.

(b) 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.

3. INSPECT POWER STEERING SOLENOID VALVE ASSEMBLY





(a) Disconnect the power steering solenoid valve connector.

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

Standard Resistance:





(c) Connect the battery positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating noise.

OK:

Valve moves and makes an operating noise.

Text in Illustration





NG -- REPLACE VANE PUMP ASSEMBLY Removal

OK -- REPLACE POWER STEERING ECU ASSEMBLY Removal