Inspection Procedure O-6
Backup Light Switch Signal Is Not Sent to the ETACS-ECUBackup Light Switch Input Circuit:
Connectors:
CIRCUIT OPERATION
The ETACS-ECU operates the rear wiper according to the input signal from the fog light switch.
TECHNICAL DESCRIPTION (COMMENT)
The backup light switch input signal is used to operate the rear wiper. If the signal is an error, the rear wiper will not operate consecutively twice when the rear wiper is on and the shift lever is moved to "R" position.
TROUBLESHOOTING HINTS
- Malfunction of the backup light switch
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors
DIAGNOSIS
Required Special Tools:
- MB991223: Test Harness Set
STEP 1. Check the backup light switch.
Q: Is the backup light switch In good condition?
YES: Go to Step 2.
NO: Repair it. The backup light switch input signal should be able to be checked and the rear wiper should work normally.
STEP 2. Check the backup light switch power supply circuit at the backup light switch connector B-37.
1. Disconnect the backup light switch connector B-37 and measure at the harness side.
2. Turn the ignition switch to "ON" position.
3. Voltage between terminal 1 and ground.
Q: Is the voltage approximately 12 volts?
YES: Go to Step 5.
NO: Go to Step 3.
STEP 3. Check the backup light switch connector B-37 for damage.
Q: Is backup light switch connector B-37 In good condition?
YES: Go to Step 4.
NO: Repair or replace it. Refer to Harness Connector Inspection. The backup light switch input signal should be able to be checked and the rear wiper should work normally.
STEP 4. Check the harness wires between backup light switch connector B-37 and ignition switch (IG1).
NOTE: After checking intermediate connector C-28 and junction block connectors C-101 and C-107, check the wires. If intermediate connector C-28 and junction block connectors C-101 and C-107 are damaged, repair or replace it. Refer to Harness Connector Inspection.
Q: Are the harness wires between backup light switch connector B-37 and ignition switch (IG1) in good condition?
YES: There is no action to be taken.
NO: Repair them. The backup light switch input signal should be able to be checked and the rear wiper should work normally.
STEP 5. Check backup light switch connector B-37 and ETACS-ECU connector C-111 for damage.
Q: Are backup light switch connector B-37 and ETACS-ECU connector C-111 in good condition?
YES: Go to Step 6.
NO: Repair or replace them. Refer to Harness Connector Inspection. The backup light switch input signal should be able to be checked and the rear wiper should work normally.
STEP 6. Check the harness wire between backup light switch connector B-37 and ETACS-ECU connector C-111.
NOTE: After checking intermediate connector C-28, check the wires. If intermediate connector C-28 is damaged, repair or replace it. Refer to Harness Connector Inspection.
Q: Is the harness wire between backup light switch connector B-37 and ETACS-ECU connector C-111 in good condition?
YES: Replace the ETACS-ECU. The backup light switch input signal should be able to be checked and the rear wiper should work normally.
NO: Repair it. The backup light switch input signal should be able to be checked and the rear wiper should work normally.