Toyota Tundra Service Manual: 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

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPAIR OR REPLACE HARNESS OR CONNECTOR

Toyota Tundra Service Manual > Power Tilt And Power Telescopic Steering Column System: Fail-safe Chart
FAIL-SAFE CHART HINT: If the power voltage to the tilt and telescopic ECU returns to normal within 10 seconds during tilt or telescopic operation, the operation will be resumed. If it returns to normal after 10 seconds have elapsed, the operation restarts when a tilt or telescopic operation signal i ...

Toyota Tundra Owners Manual