Toyota Tundra Service Manual: Problem Symptoms Table

Toyota Tundra Service Manual / Engine, Hybrid System / Wf1am Transfer / Touch Select 2-4 And High-low System / Problem Symptoms Table

PROBLEM SYMPTOMS TABLE

HINT:

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

Touch select 2-4 and high-low system

Symptom	Suspected Area	See page
When the vehicle is in the 2WD state and the transfer position switch is turned to a position other than 2WD, the 4HI and 4LO indicator lights are not illuminated	CAN communication system
	Combination meter assembly
	Transfer position switch (open circuit in LO terminal circuit or stuck OFF)
	4 wheel drive control ECU
When the vehicle is in the 4H state and the transfer position switch is turned to a position other than 4H, the 4HI indicator light is illuminated and the 4LO indicator light is not illuminated	Transfer position switch (short circuit in 2-4 or LO terminal circuit or stuck ON)
	4 wheel drive control ECU
When the vehicle is in the 4L state and the transfer position switch is turned to a position other than 4L, the 4HI indicator light is not illuminated and the 4LO indicator light is illuminated	Transfer position switch (open circuit in 2-4 terminal circuit or stuck OFF)
	4 wheel drive control ECU
	CAN communication system
The 4HI indicator light is blinking* after operation of the transfer position switch	A.D.D. actuator (differential vacuum actuator assembly)
	Transfer shift actuator assembly (transfer shift motor)
	A.D.D. actuator (differential vacuum actuator assembly) (A.D.D. shift motor)
	4 wheel drive control ECU
The 4LO indicator light is blinking* after operation of the transfer position switch	Transfer shift actuator assembly (transfer shift motor)
	4 wheel drive control ECU

*: Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)

Precaution

Shift Motor Circuit

See More:

Toyota Tundra Service Manual > How To Troubleshoot Ecu Controlled Systems: How To Proceed With Troubleshooting
HOW TO PROCEED WITH TROUBLESHOOTING 1. OPERATION FLOW HINT: Perform troubleshooting in accordance with the procedures below. The following is an outline of basic troubleshooting procedures. Confirm the troubleshooting procedures for the circuit you are working on before beginning troubleshooting. 2. ...

Toyota Tundra Service Manual: Problem Symptoms Table

Precaution

Shift Motor Circuit

See More:

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