Inspection Procedure 15: The hood latch switch signal is not received.


caution
  • Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.
  • When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition key needs to be registered to the ETACS-ECU. (If the encrypted code is not registered, the engine cannot be started. Register the encrypted code as described in Immobilizer System - How to Register Key ID .)

COMMENTS ON TROUBLE SYMPTOM


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

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


STEP 1. Check the installation condition.


Check that the hood latch switch is installed to the body correctly.

Q. Is the check result normal?

Go to Step 2.

Correct the installation condition.

STEP 2. hood latch switch check


Refer to GROUP 42A - Hood .

Q. Is the check result normal?

Go to Step 3.

Replace the hood latch switch.

STEP 3. Resistance measurement at hood latch switch connector (earth terminal)


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the hood latch switch connector (earth terminal) and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 5

Go to Step 4

STEP 4. Check of open circuit in earth line between hood latch switch connector and body earth


Q. Is the check result normal?

Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).

Repair the connector(s) or wiring harness.

STEP 5. Check of open circuit in HOOD line between hood latch switch connector and body earth


Q. Is the check result normal?

Go to Step 6

Repair the connector(s) or wiring harness.

STEP 6. M.U.T.-III data list


Check the input signals from the hood latch switch.

Item No.
 Item name
 Normal conditions
Item 266
 Hood latch switch
 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 ETACS-ECU.