Inspection procedure: 1 MPI system-related diagnostic code No.54 <except vehicles for Hong Kong and Singapore> or No.P0513 <vehicles for Hong Kong and Singapore> is set, and communication between M.U.T.-III and immobilizer cannot be established.

COMMENTS ON TROUBLE SYMPTOM
The immobilizer ECU communicates with the M.U.T.-III via the engine-ECU <M/T> or the engine-A/T-ECU. The communication error between the immobilizer ECU and the engine-ECU <M/T> or the engine-A/T-ECU may be occurred.

POSSIBLE CAUSES

  • Malfunction of immobilizer ECU power supply and earth
  • Damaged harness wires between the engine-ECU <M/T> or the engine-A/T-ECU and the immobilizer ECU

DIAGNOSTIC PROCEDURE

Step 1. Connector check: Key reminder switch connector C-308 and engine-ECU <M/T> or engine-A/T-ECU <A/T> connector C-112




Q. Are key reminder switch connector C-308 and engine-ECU <M/T> or engine-A/T-ECU <A/T> connector C-112 in good condition?

Go to Step 2.

Repair the defective connector.

Step 2. Check the harness wires between key reminder switch connector C-308 (terminal 7) and engine-ECU <M/T> or engine-A/T-ECU <A/T> connector C-112 (terminal 65).




note Prior to the wiring harness inspection, check intermediate connector C-17, and repair if necessary.

Q. Are the harness wires between key reminder switch connector C-308 (terminal 7) and engine-ECU <M/T> or engine-A/T-ECU <A/T> connector C-112 (terminal 65) in good condition?

Go to Step 3.

Repair the wiring harness.

Step 3. Check the immoblizer ECU power supply circuit and earth circuit (Refer to Inspection Procedure 4 "Check the immoblizer ECU power supply circuit and earth circuit" .)

Q. Is the check result normal?
Go to Step 4.
Repair the power supply and earth circuit to the immobilizer ECU.

Step 4. Retest the system.
Check that immobilizer ECU communicates with the M.U.T.-III.

Q. Is the check result normal?
Intermittent Malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions .)
Replace the immobilizer ECU, and then go to Step 5.

Step 5. Retest the system.
Check that immobilizer ECU communicates with the M.U.T.-III.

Q. Is the check result normal?
The procedure is complete.
Replace the engine-ECU <M/T> or engine-A/T-ECU <A/T>.