Inspection Procedure O-14

Hood Switch Input Circuit:

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

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

TROUBLESHOOTING HINTS
- Malfunction of the hood switch
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

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







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




STEP 2. Check the hood switch ground circuit at hood switch connector A-23.
1. Disconnect hood switch connector A-23 and measure at the harness side.
2. Resistance between terminal 1 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 hood switch connector A-23 for damage.
If hood switch connector A-23 is damaged, repair or replace it. Refer to Harness Connector Inspection.
The input signal from the hood 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 3.




STEP 4. Check the harness wire between hood switch connector A-23 and ground.
If the harness wire between hood switch connector A-23 and ground is damaged, repair it.
The input signal from the hood switch should be able to be checked and the theft-alarm system should be armed normally.







STEP 5. Check the hood switch connector A-23 and ETACS-ECU connector C-112 for damage.
If the hood switch connector A-23 and ETACS-ECU connector C-112 are damaged, repair or replace them. Refer to Harness Connector Inspection.
The input signal from the hood 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 hood switch connector A-23 and ETACS-ECU connector C-112.

NOTE: After checking intermediate connector C-89, check the wires. If intermediate connector C-89 is damaged, repair or replace it Refer to Harness Connector Inspection.

If the harness wires between hood switch connector A-23 and ETACS-ECU connector C-112 are damaged, repair them. The input signal from the hood 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 hood switch should be able to be checked and the theft-alarm system should be armed normally.