Toyota 4Runner: Power Steering Warning Light Circuit

Toyota 4Runner Service Manual / Steering / Power Assist Systems / Power Steering System / Power Steering Warning Light Circuit

DESCRIPTION

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

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1.	INSPECT CAN COMMUNICATION SYSTEM

(a) Check for DTCs of the CAN communication system (See page ).

Result

Result	Proceed to
DTC is not output	A
DTC is output	B

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

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

(a) Disconnect the F41 power steering ECU assembly connector.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
F41-5 (IG) - Body ground	Ignition switch ON	11 to 14 V

Standard Resistance:

Tester Connection	Condition	Specified Condition
F41-3 (GND) - Body ground	Always	Below 1 Ω

Text in Illustration

*a	Front view of wire harness connector (to Power Steering ECU Assembly)

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	PERFORM ACTIVE TEST USING TECHSTREAM (METER/GAUGE SYSTEM)

(a) Connect the Techstream to the DLC3.

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

Combination Meter

Tester Display	Test Part	Control Range	Diagnostic Note
PPS Indicator	Power steering warning light	ON or OFF	Perform the test with the vehicle stopped and the engine idling.

(d) Check that the power steering warning light operates in accordance with the Active Test.

HINT:

Reconnect the connectors and restore the vehicle to its previous condition before checking the combination meter.

OK:

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

REPLACE POWER STEERING ECU ASSEMBLY

INSPECT METER/GAUGE SYSTEM (HOW TO WITH PROCEED TROUBLESHOOTING)

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