Diagnostic Routine A

Diagnostic Routine A

Diagnostic Overview

The Alarm System Does Not Activate from an Unauthorized Entry at the Hood

Refer to Wiring Diagram Set 117 for schematic and connector information Electrical Diagrams.

Normal Operations and Fault Conditions

When the alarm system is armed, the BCM (Body Control Module) monitors the hood switch. If the hood is opened while the alarm is armed, the hood switch removes ground from the signal circuit. This signals the BCM (Body Control Module) that an unauthorized intrusion to the engine compartment has occurred and the BCM (Body Control Module) activates the alarm.

Visual Inspection and Diagnostic Pre-checks

Inspect the hood switch.

Pinpoint Test

1. RETRIEVE THE RECORDED DTCs (Diagnostic Trouble Codes) IN THE BCM (Body Control Module)

1. Ignition ON.

2. NOTE: DTC (Diagnostic Trouble Code) B1305:01 sets if the hood is open. Make sure the hood is closed prior to running the self-test.
Using a scan tool, perform the BCM (Body Control Module) self-test.

Is DTC (Diagnostic Trouble Code) B1305:01 present?








2. CHECK THE HOOD AJAR SWITCH (HOOD_SW) PID (Parameter Identification)

1. Using a scan tool, view BCM (Body Control Module) PIDs (Parameter Identifications).

2. Monitor the BCM (Body Control Module) PID (Parameter Identification) HOOD_SW while disconnecting the hood switch.

3. Disconnect: Hood Switch.

Does the BCM (Body Control Module) PID (Parameter Identification) read AJAR when the switch is disconnected?








3. CHECK THE HOOD SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

2. Disconnect: BCM (Body Control Module) C2280F.

3. Measure:





Is the resistance greater than 10,000 ohms?








4. CHECK FOR CORRECT BCM (Body Control Module) OPERATION

1. Ignition OFF.

2. Disconnect and inspect all BCM (Body Control Module) connectors.

3. Repair:

- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new pins as necessary

4. Reconnect all BCM (Body Control Module) connectors. Make sure they seat and latch correctly.

5. Operate the system and determine if the concern is still present.

Is the concern still present?