Inspection Procedure 4

INSPECTION PROCEDURE 4: Front and/or Rear Passenger's Power Window(s) do not work by means of the Power Window Main Switch.

CAUTION: Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.

CIRCUIT OPERATION
When you operate each power window switch for front or rear passengers (incorporated in the power window main switch), the corresponding power window motor operates, opening or closing each power window.

TECHNICAL DESCRIPTION (COMMENT)
If the corresponding power window opens and closes normally when each power window sub-switch is operated, the power window main switch may be defective.

TROUBLESHOOTING HINT
- The power window main switch may be defective
- The front power window sub switch may be defective
- The rear power window sub switches may be defective
- The ETACS-ECU may be defective
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector

DIAGNOSTIC PROCEDURE

Required Special Tools:
- MB992006: Extra fine probe
- MB991223: Harness set
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- B991824: Vehicles Communication Interface (V.C.I.)
- B991827: M.U.T.-III USB Cable
- B991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

STEP 1. Check the power window main switch.
Check that the driver's power window works by means of the power window main switch.

Q: Is the check result normal?

YES : Go to Step 2.

NO : Refer to inspection procedure 2 "Driver's power window does not work by means of the power window main switch". Inspection Procedure 2

STEP 2. Check the power window sub switch.
Check that each power window works by means of the respective power window sub switch when the power window lock switch is turned off.

Q: Is the check result normal?

YES : Go to Step 3.

NO : Refer to inspection procedure 3 "Relevant power window(s) does not work by means of the front and rear passenger's power window sub switches". Inspection Procedure 3

STEP 3. Check the power supply system.
With the ignition switch in the LOCK (OFF) position, check if the following function operates normally:
- Hazard warning light

Q: Is the check result normal?

YES : Go to Step 4.

NO : Refer to chassis electrical-Malfunction of ETACS-ECU power supply circuit.

STEP 4. Using scan tool MB991958, read the diagnostic trouble code.

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.







1. Connect scan tool MB991958. Refer to "How to connect scan tool (M.U.T.-III)".
2. Turn the ignition switch to the "ON" position.
3. Check whether the ETACS-ECU related DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the DTC set?

YES : Diagnose the ETACS-ECU. Refer to Local interconnect network, Diagnosis code chart.

NO : Go to Step 5.

STEP 5. Retest the system.
Check that the front and/or rear passenger's power windows work by means of the power window main switch.

Q: Is the check result normal?

YES : No action is necessary and testing is complete.

NO : Replace ETACS-ECU. Check that the power window works normally.