Inspection Procedure C-6

TECHNICAL DESCRIPTION (COMMENT)
The ETACS-ECU operates the forgotten key prevention function, based on the input signals from the following switches:
- Key reminder switch
- Driver's or passenger's door switch
- Driver's or passenger's door lock actuator switch

If the function does not work normally, a defect on the relevant circuit or the ETACS-ECU may be suspected.

TROUBLESHOOTING HINTS
- Malfunction of the key reminder switch
- Malfunction of the driver's or passenger's door switch
- Malfunction of the driver's or passenger's door lock actuator switch
- Malfunction of the ETACS-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

Check the input signal.
Check the input signals from the following switches:
- Key reminder switch
- Driver's and passenger's door switch
- Driver's and passenger's door lock actuator 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 signals checks shows a defect, check the relevant input circuit.
If no defect appears, replace the ETACS-ECU.
The forgotten key prevention function should work normally.