Inspection Procedure D-2

TECHNICAL DESCRIPTION (COMMENT)
The ETACS-ECU operates the power window timer according to the following input signals, causing the front-ECU to operate the power window relay.
- Ignition switch (IG1)
- Driver's or passenger's door switch

If the power windows do not work normally, the input signal circuit, the ETACS-ECU or the front-ECU may be defective.

TROUBLESHOOTING HINTS
- Malfunction of the driver's or passenger's door switch
- Malfunction of the ETACS-ECU
- Malfunction of the front-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 the DTC.
If the DTC sets when the ignition switch is at "LOCK" (OFF) position, carry out the troubleshooting by referring to the Diagnostic Trouble Code Chart.
If the DTC does not set, go to Step 2.

STEP 2. Check the input signal.
Check the input signals from the following switches:
- Ignition switch (IG1)
- Driver's and passenger's door switch






CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to "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.





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.
If one of the input signal checks shows a defect, check the relevant input circuit.
If all of the input signal checks show no defect, replace the ETACS-ECU or front-ECU.
The power window timer function should work normally.