Inspection Procedure C-2: 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.

  • Lamp reminder function
  • Door-ajar warning buzzer function
  • Turn-signal lamp operation sound function
  • Power window
  • Ignition key cylinder illumination lamp
  • Seat belt reminder function
  • Head and tail lamps
  • Headlamp automatic-shutdown function
  • Rear fog lamp
  • Turn signal lamp
  • Interior lamps
  • Interior lamp automatic-shutdown function

PROBABLE CAUSES

  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Connector check: D-419 ETACS-ECU connector

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

STEP 2. Voltage measurement at the D-419 ETACS-ECU connector.
(1)Remove the ETACS-ECU, and measure at the junction block side.
(2)Ignition switch: ON position
(3)Voltage between D-419 ETACS-ECU connector terminal No.8 and body earth
OK: System voltage

Q. Is the check result normal?
Go to Step 4.
Go to Step 3.

STEP 3. Check the wiring harness between D-419 ETACS-ECU connector terminal No.8 and the ignition switch (IG1).
note Prior to the wiring harness inspection, check junction block connector D-403, and repair if necessary.

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

Q. Is the check result normal?
Go to Step 4.
Repair the wiring harness.

STEP 4. Retest the system.
Check that the ignition switch (IG1) signal is received normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use troubleshooting/Inspection Service Points ).
Refer to Inspection procedure 2 "Malfunction of the ignition switch power supply system ."