Inspection Procedure H-1

Rear Wiper and Washer: Rear Wiper Does Not Work At All

Rear Wiper Motor Drive Circuit:

Connectors:

CIRCUIT OPERATION
A signal from the rear wiper switch is sent through the column-ECU inside the column switch to the ETACS-ECU. The signal turns on the relay inside the ETACS-ECU to operate the rear wiper motor.

TECHNICAL DESCRIPTION (COMMENT)
The ETACS-ECU operates the rear wiper according to the input signals from the following switches:
- Ignition switch (ACC)
- Rear wiper switch

If the rear wiper does not work normally, the relevant input signal circuit, the rear wiper motor, the column switch (windshield wiper and washer switch) or the ETACS-ECU may be defective.

TROUBLESHOOTING HINTS
- Malfunction of the rear wiper motor
- Malfunction of the column switch (windshield wiper and windshield washer switch)
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
- MB991529: Diagnostic Trouble Code Check Harness

STEP 1. Check method of the Input signal

Q: Which Is to be used, the scan tool or the voltmeter to check the input signal?
Scan tool MB991502 : Go to Step 2.
Voltmeter: Go to Step 3.

STEP 2. Check the input signal (by using scan tool MB991502).
Check the input signals from the following switches:
- Ignition switch (ACC)
- Rear wiper switch

CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.




1. Connect scan tool MB991502 to the data link connector.
2. Check that the tone alarm of scan tool MB991502 sounds when the input signal enters.

Q: Does the tone alarm of scan tool MB991502 sound when the input signal enters?

YES: Go to Step 4.

NO: Check the relevant input signal circuit.

STEP 3. Check the input signal (by using a voltmeter). Check the input signals from the following switches:
- Ignition switch (ACC)
- Rear wiper switch




1. Use special tool MB991529 to connect a voltmeter between ground terminal 4 or 5 and ETACS-ECU terminal 9 of the data link connector.
2. Check that the voltmeter indicator deflects once when the input signal enters.

Q: Does the voltmeter indicator deflect?

YES: Go to Step 4.

NO: Check the relevant input signal circuit.




STEP 4. Check the rear wiper motor.
1. Disconnect rear wiper motor connector F-07.
2. Connect a battery to the wiper motor as shown in the illustration and inspect the motor operation.

Q: Is the rear wiper motor in good condition?

YES: Go to Step 5.

NO: Repair it. The rear wiper should work normally.







STEP 5. Check the rear wiper motor connector F-07 and ETACS-ECU connector C-114 for damage.

Q: Are rear wiper motor connector F-07 and ETACS-ECU connector C-114 in good condition?

YES: Go to Step 6.

NO: Repair or replace them. Refer to Harness Connector Inspection. The rear wiper should work normally.













STEP 6. Check the harness wires between rear wiper motor connector F-07 and ETACS-ECU connector C-114.

NOTE: After checking intermediate connectors F-24 and junction block connector C-113, check the wires. If intermediate connectors F-24 and junction block connector C-113 are damaged, repair or replace them. Refer to Harness Connector Inspection

Q: Are the harness wires between rear wiper motor connector F-07 and ETACS-ECU connector C-114 in good condition?

YES: Replace the ETACS-ECU. The rear wiper should work normally.

NO: Repair them. The rear wiper should work normally.