Inspection Procedure C-7

INSPECTION PROCEDURE C-7: Central Door Locking System: Rolling lock function does not operate.

TECHNICAL DESCRIPTION (COMMENT)
The ETACS-ECU operates the rolling lock function, based on the input signals from the following switches:
- Ignition switch (IG1)
- Driver's and passenger's door switch
- Driver's or passenger's door lock actuator switch
- Speed sensor
If the function does not work normally/a defect on the relevant circuit or the ETACS-ECU may be suspected.

TROUBLESHOOTING HINTS
- The driver's or passenger's door switch may be defective.
- The driver's or passenger's door lock actuator switch may be defective.
- The speed sensor 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.

DIAGNOSIS
Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
- MB991529: Diagnostic Trouble Code Check Harness


STEP 1. Check method of the input signal

Q: Which is to be used, the scan tool or a voltmeter to check the input signal?
Scan tool MB991502 : Go to Step 2.
Voltmeter : Go to Step 3.

STEP 2. Check the input signal (by using scan tool MB991502).
Check the input signals from the following switches:
- Ignition switch (IG1)
- Driver's and passenger's door switch
- Driver's and passenger's door lock actuator switch
- Speed sensor

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

Q: Does the tone alarm of scan tool MB991502 sound when the input signal enters?

YES : Replace the ETACS-ECU. The rolling lock function should work normally.

NO :
- Scan tool MB991502 does not sound when the ignition switch is turned from "ACC" to "ON": Refer to Inspection Procedure O-2 "The ignition switch (IG1) signal is not sent to the ETACS-ECU."
- Scan tool MB991502 does not sound when the driver's or passenger's door is opened: Refer to Inspection Procedure O-8 "The driver's or passenger's door switch signal is not sent to the ETACS-ECU."
- Scan tool MB991502 does not sound when the driver's inside lock knob is locked or unlocked: Refer to Inspection Procedure O-10 "The driver's or passenger's door lock actuator switch signal is not sent to the ETACS-ECU."
- Scan tool MB991502 does not sound when the vehicle speed exceeds 24km/h (14.9 mph): Refer to Inspection Procedure O-13 "The speed sensor signal is not sent to the ETACS-ECU."

STEP 3. Check the input signal (by using a voltmeter).
Check the input signals from the following switches:
- Ignition switch (IG1)
- Driver's and passenger's door switch
- Driver's and passenger's door lock actuator switch
- Speed sensor




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.

Q: Does the voltmeter indicator deflect?

YES : Replace the ETACS-ECU. The rolling lock function should work normally.

NO :
- The voltmeter needle does not fluctuate when the ignition switch is turned from "ACC" to "ON"; Refer to Inspection Procedure O-2 "The ignition switch (IG1) signal is not sent to the ETACS-ECU."
- The voltmeter needle does not fluctuate when the driver's or passenger's door is opened: Refer to Inspection Procedure O-8 "The driver's or passenger's door switch signal is not sent to the ETACS-ECU."
- The voltmeter needle does not fluctuate when the driver's inside lock knob is locked or unlocked: Refer to Inspection Procedure O-10 "The driver's or passenger's door lock actuator switch signal is not sent to the ETACS-ECU."
- The voltmeter needle does not fluctuate when the vehicle speed exceeds 24km/h (14.9 mph): Refer to Inspection Procedure O-13 "The speed sensor signal is not sent to the ETACS-ECU."