Inspection Procedure H-4

INSPECTION PROCEDURE H-4: Rear Wiper and Washer: Rear washer does not operate.

NOTE: This troubleshooting procedure requires use of scan tool MB991958 and SWS monitor kit MB991813. For details on how to use the SWS monitor, refer to "How to use SWS monitor."

Rear Washer Motor Power Supply Circuit Part 1:

Rear Washer Motor Power Supply Circuit Part 2:

CIRCUIT OPERATION
The rear washer switch sends a signal through the column-ECU (incorporated in the column switch) to the ETACS-ECU. If the column-ECU sends a rear washer switch "ON" signal to the ETACS-ECU, the ETACS-ECU turns on the relay (incorporated in the ETACS-ECU), thus causing the rear washer motor to be turned on.

TECHNICAL DESCRIPTION (COMMENT)
If the rear washer does not work normally, the rear washer motor, the column switch (windshield wiper and washer switch) or the front-ECU may be defective.

TROUBLESHOOTING HINTS
- The rear washer motor may be defective
- The column switch (windshield wiper, washer switch) may be defective
- The ETACS-ECU may be defective

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MMB992006: Extra Fine Probe
- MMB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicles communication interface (V.C.I.)
- MB991827: MUT-III USB cable
- MB991911: MUT-III Main harness B
- MMB991813: SWS monitor kit
- MB991806: SWS monitor cartridge
- MB991812: SWS monitor harness (for column-ECU)
- MB991922: Probe harness

STEP 1. Verify the rear wiper.

Q: Does the rear wiper operate?

YES: Go to Step 2.

NO: Refer to Inspection Procedure H-1 "Rear wiper does not work at all."

STEP 2. Check the input signal by using "FUNCTION DIAG." menu of the SWS monitor.

Set each switch to the following condition before checking input signals from the rear washer switch:
- Ignition switch: ACC
- Rear washer switch: ON

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958. Connect special tool MB991910 before connecting special tool MB991812. Be sure to connect special tool MB991806 after turning on special tool MB991824.







1. Connect the special tool. Refer to "How to connect SWS monitor."
2. Operate the scan tool MB991958 according to the procedure below to display "REAR WASHER."
a. Select "System select."
b. Select "SWS."
c. Select "SWS MONITOR."
d. Select "Function Diag."
e. Select "REAR WIPER."
f. Select "REAR WASHER."




3. Check that normal condition is displayed for the item described in the table.

Q: Is normal condition displayed?

YES: Go to Step 3.

NO: Refer to Inspection Procedure M-7 "ETACS-ECU does not receive a signal from the rear washer switch."




STEP 3. Check the rear washer motor connector A-32 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is rear washer motor connector A-32 in good condition?

YES: Go to Step 4.

NO: Repair or replace the damaged component(s). Refer to Harness Connector Inspection. Verify that the rear washer works normally.

STEP 4. Check the rear washer motor.




1. Disconnect rear washer motor connector A-32. (2) Fill the washer tank with washer fluid.




3. When battery voltage is applied between terminals 1 and 2, washer fluid should spray out.

Q: Does the rear washer motor operate normally?

YES: Go to Step 5.

NO: Replace the rear washer motor. Verify that the rear washer works normally.

STEP 5. Check the ground circuit to the rear washer motor. Measure the resistance at the rear washer motor connector A-32.




1. Disconnect rear washer motor connector A-32 and measure the resistance available at the wiring harness side of the connector.




2. Measure the resistance value between terminal 1 and ground.
- The resistance should equal 2 ohms or less.

Q: Is the measured resistance 2 ohms or less?

YES: Go to Step 7.

NO: Go to Step 6.




STEP 6. Check the wiring harness between rear washer motor connector A-32 (terminal 1) and ground.

Q: Is the wiring harness between rear washer motor connector A-32 (terminal 1) and ground in good condition?

YES: No action is necessary and testing is complete.

NO: The wiring harness may be damaged or the connector may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the rear washer works normally.




STEP 7. Check the ETACS-ECU connector C-219 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q: Is ETACS-ECU connector C-219 in good condition?

YES: Go to Step 8.

NO: Repair or replace the damaged component(s). Refer to Harness Connector Inspection. Verify that the rear washer works normally.










STEP 8. Check the wiring harness between rear washer motor connector A-32 (terminal 2) and ETACS-ECU connector C-219 (terminal 23).

NOTE: Also check intermediate connector C-24 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If junction block intermediate connector C-24 is damaged, repair or replace damaged component(s) as described in Harness Connector Inspection.

Q: Is the wiring harness between rear washer motor connector A-32 (terminal 2) and ETACS-ECU connector C-219 (terminal 23) in good condition?

YES: Replace the ETACS-ECU. When the ETACS-ECU is replaced, register the encrypted code. Refer to Encrypted Code Registration Criteria Table in Antitheft and Alarm Systems. Verify that the rear washer works normally.

NO: The wiring harness may be damaged or the connector may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the rear washer works normally.