Inspection Procedure J-3: The ignition switch (IG1) signal is not received.


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


COMMENTS ON TROUBLE SYMPTOM


Input signal from the ignition switch (IG1) is used to operate the functions below. If the signal is abnormal, these functions will not work normally.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list
Check the power supply voltage of the ETACS-ECU.

  • Turn the ignition switch to the "ON" position
Item No.
 Item name
 Normal condition
31
 Battery voltage (IG1)
 System voltage
OK: Normal condition is displayed.

Q. Is the check result normal?
Go to Step 4.
Go to Step 2.

STEP 2. Connector check: B-233 ETACS-ECU connector


Q. Is the check result normal?

Go to Step 3.

Repair the defective connector.

STEP 3. Check the wiring harness between B-233 ETACS-ECU connector terminal No.52 and the ignition switch (IG1).




note Prior to the wiring harness inspection, check joint connector B-26, junction block connectors B-229 and B-231, and repair if necessary.

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

Q. Is the check result normal?

Perform troubleshooting for ignition switch. Refer to GROUP 54A - Ignition switch . Go to Step 4.

Repair the wiring harness.

STEP 4. M.U.T.-III data list
Check the input signal from the ignition switch (IG1).

  • Turn the ignition switch to the "ON" position.
Item No.
 Item name
 Normal condition
30
 Ignition switch (IG1)
 ON
31
 Battery voltage (IG1)
 System voltage
OK: Normal conditions are displayed for all the items.

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. Then perform the variant coding and write the VIN data (Refer to GROUP 00, Precautions Before Service - How to Perform Variant Coding ).