Description

Theft-deterrent siren or theft-deterrent horn sounded

Possible cause

• Wiring harness malfunction

• Malfunction in switch which triggers system

• BCM malfunction

• Customer’s mis-operation or misunderstanding

System wiring diagram

Not applicable

Step

Inspection

Action

1

VERIFY DTCs

• Perform the DTC inspection for the BCM using the M-MDS.

  (See DTC INSPECTION [BCM].)

• Are any DTCs displayed?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [BCM].)

No

Go to the next step.

2

VERIFY OPERATION RECORD

• Has the operation record been stored?

  (See THEFT-DETERRENT SYSTEM OPERATION RECORD.)

Yes

Go to the next step.

No

Diagnosis completed (theft-deterrent system does not operate).

3

VERIFY CONDITION DURING THEFT-DETERRENT SYSTEM OPERATION

• Is the condition during theft-deterrent operation “Alarm” or “Arming”?

Yes

Go to the next step.

No

Inspect the BCM. If there is any malfunction, replace it.

(See BODY CONTROL MODULE (BCM) INSPECTION.)

4

DETERMINE IF MALFUNCTION CAUSE IS SYSTEM

• Verify what triggered the theft-deterrent system according to the trigger record, and inspect the switch which triggered the system and the related wiring harness.

• Is the switch or related wiring harness normal?

Yes

System is normal (explain to the customer that the cause is customer’s mis-operation).

No

Replace the malfunctioning part.