Inspection Procedure C-3: The "R" position 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 back-up lamp switch <M/T> or inhibitor switch <A/T> is used to operate the rear wiper. If the signal is abnormal, the rear wiper will not work normally.

PROBABLE CAUSES

  • Malfunction of the back-up lamp switch <M/T>
  • Malfunction of the inhibitor switch <A/T>
  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Connector check: D-421 ETACS-ECU connector, C-17 back-up lamp switch connector <M/T> and C-05 inhibitor switch connector <A/T>

Q. Is the check result normal?
YES <Vehicles for M/T> : Go to Step 2.
YES <Vehicles for A/T> : Go to Step 7.
NO <The connectors are not in good condition.> : Repair the defective connector.

STEP 2. Check the back-up lamp switch
Check the back-up lamp switch (Refer to GROUP 22B - Transmission ).

Q. Is the check result normal?
Go to Step 3.
Replace the back-up lamp switch.

STEP 3. Voltage measurement at the D-421 ETACS-ECU connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Ignition switch: ON
(3)Shift position: R position
(4)Voltage between D-421 ETACS-ECU connector terminal No.39 and body earth
OK: System voltage

Q. Is the check result normal?
Replace the ETACS-ECU.
Go to Step 4.

STEP 4. Voltage measurement at the C-17 back-up lamp switch connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Ignition switch: ON
(3)Voltage between C-17 back-up lamp switch connector terminal No.2 and body earth
OK: System voltage

Q. Is the check result normal?
Go to Step 5.
Go to Step 6.

STEP 5. Check the wiring harness between C-17 back-up lamp switch connector terminal No.1 and D-421 ETACS-ECU connector terminal No.39.
note Prior to the wiring harness inspection, check intermediate connectors D-225 and D-230, and repair if necessary.

  • Check the input line for open and short circuit.

Q. Is the check result normal?
Go to Step 12.
Repair the wiring harness.

STEP 6. Check the wiring harness between C-17 back-up lamp switch connector terminal No.2 and the ignition switch (IG1).
note Prior to the wiring harness inspection, check intermediate connectors D-225, D-229, junction block connectors D-401 and D-403, and repair if necessary.

  • Check the power supply line to the ignition switch (IG1) for open circuit.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use troubleshooting/Inspection Service Points ).
Repair the wiring harness.

STEP 7. Check the inhibitor switch
Check the inhibitor switch (Refer to GROUP 23A - On-vehicle Service ).

Q. Is the check result normal?
Go to Step 8.
Replace the inhibitor switch.

STEP 8. Voltage measurement at the D-421 ETACS-ECU connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Ignition switch: ON
(3)Shift position: R position
(4)Voltage between D-421 ETACS-ECU connector terminal No.39 and body earth
OK: System voltage

Q. Is the check result normal?
Replace the ETACS-ECU.
Go to Step 9.

STEP 9. Voltage measurement at the C-05 inhibitor switch connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Ignition switch: ON
(3)Voltage between C-05 inhibitor switch connector terminal No.3 <3200> or 7 <3800> and body earth
OK: System voltage

Q. Is the check result normal?
Go to Step 10.
Go to Step 11.

STEP 10. Check the wiring harness between C-05 inhibitor switch connector terminal No.4 <3200> or 8 <3800> and D-421 ETACS-ECU connector terminal No.39.
note Prior to the wiring harness inspection, check intermediate connectors D-225 and D-230, and repair if necessary.

  • Check the input line for open and short circuit.

Q. Is the check result normal?
Go to Step 12.
Repair the wiring harness.

STEP 11. Check the wiring harness between C-05 inhibitor switch connector terminal No. 3 <3200> or 7 <3800> and the ignition switch (IG1).
note Prior to the wiring harness inspection, check intermediate connectors D-225, D-229, junction block connectors D-401 and D-403, and repair if necessary.

  • Check the power supply line to the ignition switch (IG1) for open circuit.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use troubleshooting/Inspection Service Points ).
Repair the wiring harness.

STEP 12. Retest the system.
Check that the back-up lamp switch <M/T> or inhibitor switch <A/T> 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 ).
Replace the ETACS-ECU.