Toyota Tundra Service Manual: Diagnosis System

DIAGNOSIS SYSTEM

1. DESCRIPTION

The 4 wheel drive control ECU records DTCs when the ECU detects a malfunction in the ECU itself or in system circuits.

The DTCs can be read through the DLC3 of the vehicle. When the system seems to be malfunctioning, use the Techstream to check for malfunctions and perform troubleshooting.

2. CHECK DLC3

(a) Inspect the battery voltage.

Standard voltage:

11 to 14 V

If the voltage is below 11 V, recharge the battery before proceeding.

(b) Check the DLC3 (See page ).

3. FUNCTION OF INDICATOR LIGHT

(a) When a problem occurs in the touch select 2-4 and high-low system, the 4HI and 4LO indicator lights on the combination meter assembly rapidly blink* to inform the driver of the problem.

  • *: 0.25 second intervals (0.25 seconds on and 0.25 seconds off)
    4WD Control Switch Circuit

    Diagnostic Trouble Code Chart

    See More:

    Toyota Tundra Service Manual > Automatic Transmission System: Shift Solenoid "B" Control Circuit Low (Shift Solenoid Valve S2) (P0976,P0977)
    DESCRIPTION Shifting from 1st to 6th is performed in combination with ON and OFF operation of the shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR, which are controlled by the ECM. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shif ...

    Toyota Tundra Owners Manual

    Toyota Tundra Service Manual

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