Inspection Procedure 5: Check the power supply and earth circuit to the immobilizer-ECU. <3200>


















COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Connector check: D-126 immobilizer-ECU connector

Q. Is the check result normal?
Go to Step 2.
Repair the defective connector.

STEP 2. Voltage measurement at immobilizer-ECU connector D-126 in order to check the battery circuit of power supply system to the immobilizer-ECU.


(1)Disconnect the immobilizer-ECU connector D-126 and measure the voltage at immobilizer-ECU connector D-126 harness side.
(2)Turn the ignition switch to “ON” position.
(3)Measure the voltage between terminal 1 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 5.
Go to Step 3.

STEP 3. Connector check: B-15X engine control relay connector

Q. Is the check result normal?
Go to Step 4.
Repair the defective connector.

STEP 4. Check the wiring harness between B-15X engine control relay connector terminal No. 1 and D-126 immobilizer-ECU connector terminal No.1.
note Prior to the wiring harness inspection, check joint connector D-111, intermediate connector D-229, and repair if necessary.

  • Check the power supply line for open circuit and short circuit.

Q. Is the check result normal?
Go to Step 5.
Repair the wiring harness.

STEP 5. Resistance measurement at immobilizer-ECU connector D-126 to check the earth circuit to the immobilizer-ECU connector.
(1)Disconnect the immobilizer-ECU connector D-126 and measure the resistance at immobilizer-ECU connector D-126 harness side.
(2)Turn the ignition switch to “ON” position.
(3)Measure the resistance between terminal 2 and earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
The procedure is complete.
Go to Step 6.

STEP 6. Check the wiring harness between D-126 immobilizer-ECU connector terminal No.2 and earth.

  • Check the earth wires for open circuit.

Q. Is the check result normal?
The procedure is complete.
Repair the wiring harness.