Inspection Procedure D-1

Power window relay: Power windows do not work at all.

Power Window Relay Circuit:

Connector:

CIRCUIT OPERATION
- The power window relay is controlled by the front-ECU and the ETACS-ECU
- The front-ECU operates the power window relay if the front-ECU receives request signal from the ETACS-ECU, or ignition switch (IG1) signal from the front-ECU itself.

TECHNICAL DESCRIPTION (COMMENT)
The power window relay or the front-ECU may be defective.

TROUBLESHOOTING HINTS
- Malfunction of the power window relay
- Malfunction of the front-ECU
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tool:
- MB991223: Test Harness Set







STEP 1. Check the power window relay.

Q: Is the power window relay in good condition?

YES: Go to Step 2.
NO: Replace it. The power windows should work normally.

STEP 2. Check the power window relay power supply circuit at the power window relay connector A-04X.
1. Disconnect the power window relay connector A-04X and measure at the relay box side.




2. Measure the voltages between terminal 1, 5 and ground.

Q: Are the voltages approximately 12 volts (battery positive voltage)?

YES: Go to Step 5.
NO: Go to Step 3.




STEP 3. Check the power window connector A-04X for damage.

Q: Is power window connector A-04X in good condition?

YES: Go to Step 4.
NO: Repair or replace it. Refer to Harness Connector Inspection. The power windows should work normally.




STEP 4. Check the harness wire between power window relay connector A-04X and fusible link (4).

Q: Is the harness wire between power window relay connector A-04X and fusible link (4) in good condition?

YES: There is no action to be taken.
NO: Repair it. The power windows should work normally.

STEP 5. Check the power window main switch ground circuit at the power window main switch connector E-12.
1. Disconnect the power window main switch connector E-12 and measure at the harness side.




2. Measure the resistance between terminal 9 and ground.

Q: Is the resistance less than 2 ohm?

YES: Go to Step 8.
NO: Go to Step6.




STEP 6. Check power window main switch connector E-12 for damage.

Q: Is power window main switch connector E-12 in good condition?

YES: Go to Step 7.
NO: Repair or replace it. Refer to Harness Connector Inspection. The power windows should work normally.







STEP 7. Check the harness wires between power window main switch connector E-12 and ground.

NOTE: After checking intermediate connector C-211, check the wires. If intermediate connector C-211 is damaged, repair or replace it. Refer to Harness Connector Inspection.

Q: Are the harness wires between power window main switch connector E-12 and ground in good condition?

YES: There is no action to be taken.
NO: Repair them. The power windows should work normally.




STEP 8. Check the power window relay connector A-04X and front-ECU connector A-09X for damage.

Q: Are power window relay connector A-09X and front-ECU connector A-09X in good condition?

YES: Go to Step 9.
NO: Repair or replace them. Refer to Harness Connector Inspection. The power windows should work normally.




STEP 9. Check the harness wire between power window relay connector A-04X and front-ECU connector A-09X.

Q: Is the harness wire between power window relay connector A-04X and front-ECU connector A-09X in good condition?

YES: Go to Step 10.
NO: Repair it. The power windows should work normally.







STEP 10. Check the power window relay connector A-04X and power window main switch connector E-12 for damage.

Q: Are power window relay connector A-04X and power window main switch connector E-12 in good condition?

YES: Go to Step 11.
NO: Repair or replace them. Refer to Harness Connector Inspection. The power windows should work normally.










STEP 11. Check the harness wires between power window relay connector A-04X and power window main switch connector E-12.

NOTE: After checking intermediate connectors C-209 and C-211, check the wires. If intermediate connectors C-209 and C-211 are damaged, repair or replace them. Refer to Harness Connector Inspection.

Q: Are the harness wires between power window relay connector A-04X and power window main switch connector E-12 in good condition?

YES: Replace the ETACS-ECU. The power windows should work normally.
NO: Repair them. The power windows should work normally.