Inspection procedure 2: The 4LLc Switch Signal is not Received. <Vehicles with 4WD and 5M/T>

caution

Whenever the ECU is replaced, ensure that the input signal circuit is normal.

COMMENTS ON TROUBLE SYMPTOM

If there is an error to the 4LLc switch input signal, the 4LLc switch signal is no longer output to the communication line.

PROBABLE CAUSES

Malfunction of 4LLc switch
Malfunction of the gateway-ECU
Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

Check the input signals from the centre differential lock operation detection switch.

Operate the transfer shift position: 4LLc.

Item No.	Item name	Normal condition
7	Indicator SW (Low gear)	OFF to ON

OK: Normal condition is displayed.

Q. Is the check result normal?

Go to Step 3.

Go to Step 2.

STEP 2. Check the wiring harness between 4LLc switch connector and the gateway-ECU connector.

Check of short to power supply, short to earth, and open circuit between gateway-ECU connector and 4LLc switch

Q. Is the check result normal?

Go to Step 3.

Repair the connector(s) or wiring harness.

STEP 3. Check the 4WD indicator-ECU

Refer to GROUP 22A - 4LLc Switch Continuity Check

Q. Is the check result normal?

Go to Step 4.

Replace the 4LLc switch.

STEP 4. M.U.T.-III data list

Operate the transfer shift position: 4LLc.

Item No.	Item name	Normal condition
7	Indicator SW (Low gear)	OFF to ON

OK: Normal condition is displayed.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction).

Replace the gateway-ECU.