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.
Power window Circuit (Part 1):
Power window Circuit (Part 2):
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)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: 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 (LIN), Diagnostic trouble code chart.
NO: Go to Step 5.
STEP 5. Check power window main switch connector E-15 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is power window main switch connector E-15 in good condition?
YES: Go to Step 6.
NO: Repair or replace the damaged component(s). Refer to general (electrical), Harness Connector Inspection. When the power window main switch is operated, the front and/or rear passenger's power windows should raise and lower normally.
STEP 6. Check the ETACS-ECU connector C-315 line circuit to the power window main switch. Measure the voltage at power window main switch connector E-15.
1. Disconnect power window main switch connector E-15 and measure the voltage available at the wiring harness side of the connector.
2. Measure the voltage between terminal 4 and ground.
- The voltage should measure approximately 12 volts (battery positive voltage).
Q: Is the measured voltage approximately 12 volts (battery positive voltage)?
YES: Go to Step 9.
NO: Go to Step 7.
STEP 7. Check ETACS-ECU connector C-315 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is ETACS-ECU connector C-315 in good condition?
YES: Go to Step 8.
NO: Repair or replace the damaged component(s). Refer to general (electrical), Harness Connector Inspection. When the power window main switch is operated, the front and/or rear passenger's power windows should raise and lower normally.
STEP 8. Check the wiring harness between ETACS-ECU connector C-315 (terminal No. 8) and power window main switch connector E-15 (terminal No. 4).
NOTE: Also check intermediate connector C-128. If intermediate connector C-128 is damaged, repair or replace the damaged component(s) as described in general (electrical), Harness Connector Inspection.
Q: Is the wiring harness between ETACS-ECU connector C-315 (terminal No. 8) and power window main switch connector E-15 (terminal No. 4) in good condition?
YES: No action is necessary and testing is complete.
NO: The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. When the When the power window main switch is operated, the front and/or rear passenger's power windows should raise and lower normally.
STEP 9. Retest the system.
Replace the power window main switch. 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.