Toyota Tundra Service Manual: IG Power Source Circuit

Toyota Tundra Service Manual / Steering / Steering Column / Power Tilt And Power Telescopic Steering Column System / IG Power Source Circuit

DESCRIPTION

When the ignition switch is turned to on, the IG power source circuit supplies positive (+) voltage to the multiplex tilt and telescopic ECU.

The multiplex tilt and telescopic ECU also receives ignition switch signals via this circuit.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

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

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU - BATTERY)

(a) Disconnect the J174 multiplex tilt and telescopic ECU connector.

*a

Front view of wire harness connector

(to Multiplex Tilt and Telescopic ECU)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

J174-10 (IG) - Body ground

Ignition switch ON

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

2.

CHECK HARNESS AND CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU - BODY GROUND)

(a) Disconnect the J174 multiplex tilt and telescopic ECU connector.

*a

Front view of wire harness connector

(to Multiplex Tilt and Telescopic ECU)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J174-1 (GND) - Body ground

Always

Below 1 Ω

J174-8 (GND2) - Body ground

Always

Below 1 Ω
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
    How To Proceed With Troubleshooting

    Parts Location

    See More:

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