4WD Indicator Light does not Come ON
UF1AE TRANSFER: FOUR WHEEL DRIVE CONTROL SYSTEM: 4WD Indicator Light does not Come ON
4WD Indicator Light does not Come ON
DESCRIPTION
The 4WD control ECU is connected to the combination meter assembly via CAN and Multiplex communications.
If any of the following is detected, the multi-information display indicates a malfunction in the four-wheel drive control system.
- There is a malfunction in the 4WD control ECU internal circuit.
- A low voltage is applied to the power source for the 4WD control ECU.
- There is a malfunction in the CAN communication system.
- There is a malfunction in the brake control system.
- During fail-safe function.
HINT: When any of the DTCs C1297/97, U0100/85, and U0126/84 is detected, the 4WD indicator light will not come on.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT: Check the condition of each related circuit connector before troubleshooting Electronic Circuit Inspection Procedure.
PROCEDURE
1. CHECK DTC
(a) Check the output DTC Reading and Clearing Diagnostic Trouble Codes.
Result:
HINT: When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.
C -- REPAIR CIRCUIT INDICATED BY OUTPUT CODE
B -- REPAIR CIRCUIT INDICATED BY OUTPUT CODE
A -- Continue to next step.
2. PERFORM ACTIVE TEST USING TECHSTREAM (4WD INDICATOR LIGHT)
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Select the "Active Test" on the Techstream and operate the 4WD indicator light using the Techstream Scan Tool Testing and Procedures.
ACTIVE TEST:
(d) Check that 4WD indicator light displayed in the multi-information display when using the Techstream.
OK:
The 4WD indicator light displayed on the multi-information display is turned on or off by the Techstream operation.
NG -- CHECK CAN COMMUNICATION SYSTEM
OK -- REPLACE 4WD CONTROL ECU
3. CHECK CAN COMMUNICATION SYSTEM
(a) Check if the CAN communication system DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- REPAIR CIRCUIT INDICATED BY OUTPUT CODE
A -- Continue to next step.
4. CHECK MULTIPLEX COMMUNICATION SYSTEM
(a) Check if the multiplex communication system DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- REPAIR CIRCUIT INDICATED BY OUTPUT CODE
A -- Continue to next step.
5. CHECK COMBINATION METER ASSEMBLY
(a) Troubleshoot the combination meter assembly system How To Proceed With Troubleshooting.
Result:
The combination meter assembly system is normal.
NG -- REPLACE COMBINATION METER ASSEMBLY
OK -- REPLACE 4WD CONTROL ECU