Inspection Procedure N-1
Theft-alarm System: Theft-alarm System is not Armed (Theft-alarm Indicator Light does not Illuminate)
NOTE: This troubleshooting requires use of scan tool MB991502 and SWS monitor kit MB991862. For details of how to use the SWS monitor, refer to "How to use SWS monitor."
Theft-alarm Indicator Light Circuit:
Connector:
CIRCUIT OPERATION
- When the ETACS-ECU receives a "LOCK" signal from the door lock actuator switch, it illuminates the security indicator light for approximately 18 seconds, and then set the theft-alarm system.
- The ETACS-ECU sets the theft-alarm system according to the input signals from the following signals:
- Ignition key reminder switch: ON
- Driver's and front passenger's door switch: OFF
- Driver's and front passenger's door lock key cylinder switch: OFF
- Driver's and front passenger's doors actuator switch: LOCK
- Liftgate latch switch: OFF
- Liftgate lock key cylinder switch: OFF
- Trunk lid latch switch: OFF
- Trunk lid lock key cylinder switch: OFF
- Hood switch: OFF
- Transmitter switch: LOCK
- Vehicle condition:
- Ignition key: Removed from the ignition key cylinder
- All doors: Closed
- Driver's and front passenger's door lock key cylinder: Not being operated
- Liftgate: Opened
- Liftgate lock key cylinder: Not operating
- Trunk lid: Closed
- Trunk lid lock key cylinder: Not operating
- Hood: Closed
- Transmitter: Turn to the "LOCK" position
TECHNICAL DESCRIPTION (COMMENT)
If the theft-alarm system is set normally, the input signal circuit, the "SECURITY" indicator light or the ETACS-ECU may be defective.
TROUBLESHOOTING HINTS
- Malfunction of the theft-alarm indicator light
- Malfunction of the ignition key reminder switch
- Malfunction of the driver's or front passenger's door switch
- Malfunction of the driver's or front passenger's door lock key cylinder switch
- Malfunction of the driver's and front passenger's door lock actuator switch
- Malfunction of the liftgate latch switch
- Malfunction of the liftgate lock key cylinder switch signal
- Malfunction of the trunk lid latch switch
- Malfunction of the trunk lid lock key cylinder switch signal
- Malfunction of the hood switch
- Malfunction of the transmitter
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors
DIAGNOSIS
Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
- MB991862: SWS Monitor Kit
STEP 1. Check the power supply circuit to the ETACS-ECU.
Do the hazard warning lights work normally when the ignition switch is turned to the "LOCK" (OFF) position?
Q: Do the hazard warning lights work normally?
YES: Go to Step 2.
NO: Refer to Inspection Procedure A-3 "Communication with the ETACS-ECU is impossible."
STEP 2. Check at ETACS-ECU connector C-118 in order to check the theft-alarm indicator light circuit.
1. Disconnect ETACS-ECU connector C-118, and measure at the wiring harness side.
2. The theft-alarm indicator light should illuminate when terminal 74 is grounded.
Q: Does the theft-alarm indicator light illuminate?
YES: Go to Step 9.
NO: Go to Step 3.
STEP 3. Check the theft-alarm indicator light.
1. Remove the combination meter. Refer to combination meter.
2. Disconnect combination meter connector C-42.
3. The theft-alarm indicator light should illuminate when battery voltage is applied between terminals 31 and 32.
Q: Does the theft-alarm indicator light illuminate?
YES: Go to Step 4.
NO: Replace the theft-alarm indicator light. The theft-alarm indicator light should illuminate, and the theft-alarm system should be set normally.
STEP 4. Check at combination meter connector C-42 in order to check the battery power supply line to the theft alarm indicator light circuit.
1. Disconnect combination meter connector C-42, and check at the wiring harness side.
2. Measure the voltage between terminal 32 and ground.
- The measured value should be approximately 12 volts (battery positive voltage).
Q: Does the measured voltage correspond with this range?
YES: Go to Step 7.
NO: Go to Step 5.
STEP 5. Check combination meter connector C-42 for damage.
Q: Is combination meter connector C-42 in good condition?
YES: Go to Step 6.
NO: Repair or replace the connector. Refer to Harness Connector Inspection. The theft-alarm indicator light should illuminate, and the theft-alarm system should be set normally.
STEP 6. Check the wiring harness between combination meter connector C-42 and the battery.
NOTE: Also check joint connector C-78 and intermediate connector C-89. If joint connector C-78 or intermediate connectors C-89 is damaged, repair or replace the connector as described in Harness Connector Inspection.
Q: Is the wiring harness between combination meter connector C-42 and the battery in good condition?
YES: No action to be taken.
NO: Repair the wiring harness. The theft-alarm indicator light should illuminate, and the theft-alarm system should be set normally.
STEP 7. Check combination meter connector C-42 and ETACS-ECU connector C-118 for damage.
Q: Are combination meter connector C-42 and ETACS-ECU connector C-118 in good condition?
YES: Go to Step 8.
NO: Repair or replace the connector. Refer to Harness Connector Inspection. The theft-alarm indicator light should illuminate, and the theft-alarm system should be set normally.
STEP 8. Check the wiring harness between combination meter connector C-42 and ETACS-ECU connector C-118.
Q: Is the wiring harness between combination meter connector C-42 and ETACS-ECU connector C-118 in good condition?
YES: No action to be taken.
NO: Repair the wiring harness. The theft-alarm indicator light should illuminate, and the theft-alarm system should be set normally.
STEP 9. Check the input signal by using service data of the SWS monitor.
Open both front doors in order to check the input signals from the driver's and the front passenger's door switches.
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. Also connect SWS monitor kit MB991862 after turning on scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Connect SWS monitor kit MB991862 to the column switch connector.
3. Select "ETACS-ECU" (DATA LIST), and check that normal conditions are displayed on the items described in the table.
Q: The scan tool shows the respective normal condition for item "DR DOOR SW" and "PASS DOOR SW."
YES: Go to Step 10.
NO: Refer to Inspection Procedure O-6 "ETACS-ECU does not receive a signal from the driver's or front passenger's door switch."
STEP 10. Check the input signal (by using the Pulse Check).
Check the input signals from the following switches:
- Key reminder switch
- Driver's and front passenger's door lock actuator switch
- Driver's and front passenger's door lock key cylinder switch
- Hood switch
- Liftgate latch switch
- Liftgate lock key cylinder switch
- Trunk lid latch switch
- Trunk lid lock key cylinder switch
If the switches (see table), which are applicable for the input signal check, are operated, check if scan tool MB991502 sounds or not.
Q: When the key reminder switch, driver's and front passenger's door lock actuator switches, driver's and front passenger's door look key cylinder switches, hood switch, liftgate latch switch
YES: Replace the ETACS-ECU. The theft-alarm indicator light should illuminate, and the theft-alarm system should be set normally.
NO:
- Scan tool MB991502 does not sound when the key reminder switch is operated: Refer to Inspection Procedure P-1 "ETACS-ECU does not receive a signal from the key reminder switch."
- Scan tool MB991502 does not sound when the driver's and the front passenger's door lock actuator switches are operated: Refer to Inspection Procedure P-5 "ETACS-ECU does not receive signals from the driver's or the front passenger's door lock actuator switches."
- Scan tool MB991502 does not sound when the driver's and the front passenger's door lock actuator switches are operated: Refer to Inspection Procedure P-4 "ETACS-ECU does not receive signals from the driver's and the front passenger's door lock key cylinder switches."
- Scan tool MB991502 does not sound when the hood switch is operated: Refer to Inspection Procedure P-8 "ETACS-ECU does not receive a signal from the hood switch."
- When the liftgate latch switch
- When the liftgate lock key cylinder switch