Inspection Procedure O-15

Liftgate Latch Switch Input Circuit:

Connector: F-16:

CIRCUIT OPERATION
The ETACS-ECU uses the input signal from the liftgate latch switch to arm the theft-alarm system.

TECHNICAL DESCRIPTION (COMMENT)
The liftgate latch switch input signal is used to arm the theft-alarm system. If the signal fails, the theft-alarm system will not be armed normally.

TROUBLESHOOTING HINTS
- Malfunction of the liftgate latch
- 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







STEP 1. Check the liftgate latch switch.
If the liftgate latch switch is damaged, replace it. The input signal from the liftgate latch switch should be able to be checked and the theft-alarm system should be armed normally.
If the liftgate latch switch is in good condition, go to Step 2.




STEP 2. Check the liftgate latch switch ground circuit at liftgate latch switch connector F-16.
1. Disconnect liftgate latch switch connector F-16 and measure at the harness side.
2. Resistance between terminal 2 and ground.
- Should be less than 2 Ohms.
If open circuit, go to Step 3.
If less than 2 Ohms, go to Step 5.




STEP 3. Check liftgate latch switch connector F-16 for damage.
If liftgate latch switch connector F-16 is damaged, repair or replace it. Refer to Harness Connector Inspection.
The input signal from the liftgate latch switch should be able to be checked and the theft-alarm system should be armed normally.
If the connector is in good condition, go to Step 4.




STEP 4. Check the harness wire between liftgate latch switch connector F-16 and ground.
If the harness wire between liftgate latch switch connector F-16 and ground is damaged, repair it.
The input signal from the liftgate latch switch should be able to be checked and the theft-alarm system should be armed normally.







STEP 5. Check the liftgate latch switch connector F-16 and ETACS-ECU connector C-112 for damage.
If the liftgate latch switch connector F-16 and ETACS-ECU connector C-112 are damaged, repair or replace them. Refer to Harness Connector Inspection. The input signal from the liftgate latch switch should be able to be checked and the theft-alarm system should be armed normally.
If the connectors are in good condition, go to Step 6.










STEP 6. Check the harness wires between liftgate latch switch connector F-16 and ETACS-ECU connector C-112.

NOTE: After checking intermediate connector C-90, check the wires. If intermediate connector C-90 is damaged, repair or replace it. Refer to Harness Connector Inspection.

If the harness wires between liftgate latch switch connector F-16 and ETACS-ECU connector C-112 are damaged, repair them.
The input signal from the liftgate latch switch should be able to be checked and the theft-alarm system should be armed normally.

If the harness wires are in good condition, replace the ETACS-ECU.
The input signal from the liftgate latch switch should be able to be checked and the theft-alarm system should be armed normally.