Pinpoint Test B: The Alarm System Does Not Activate From An Unauthorized Entry At The Hood

Anti-Theft

Pinpoint Test B: The Alarm System Does Not Activate From An Unauthorized Entry At The Hood

Refer to Wiring Diagram Set 117, Remote Keyless Entry and Alarm for schematic and connector information Electrical Diagrams.

Normal Operation

When the alarm system is armed, the Body Control Module (BCM) monitors the hood ajar switch. If the hood is opened while the alarm is armed, the hood ajar 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 alarm is activated.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Hood switch (part of the hood latch)

- BCM (Body Control Module)

PINPOINT TEST B : THE ALARM SYSTEM DOES NOT ACTIVATE FROM AN UNAUTHORIZED ENTRY AT THE HOOD

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

B1 RETRIEVE THE RECORDED DTCs IN THE BCM (Body Control Module)

NOTE: DTC P254F:00 sets if the hood is open. Make sure the hood is closed prior to running the self-test.

- Retrieve the recorded DTCs from the BCM (Body Control Module) self-test.

Is DTC P254F:00 present?

Yes
GO to Pinpoint Test C Pinpoint Test C: DTC P254F:00.

No
GO to B2.

B2 CHECK THE HOOD SWITCH (HOOD_SW) PID

- Enter the following diagnostic mode on the scan tool: BCM (Body Control Module) DataLogger.

- Monitor the BCM (Body Control Module) PID (HOOD_SW) while disconnecting the hood switch.

- Disconnect: Hood Switch C127.

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

Yes
INSTALL a new hood latch. TEST the system for normal operation.

No
GO to B3.

B3 CHECK THE HOOD SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND

- Ignition OFF.

- Disconnect: BCM (Body Control Module) C2280D.

- Measure the resistance between the hood switch C127-2, circuit CPL25 (BU/OG), harness side and ground.





Is the resistance greater than 10,000 ohms?

Yes
GO to B4.

No
REPAIR circuit CPL25 (BU/OG) for a short to ground. TEST the system for normal operation.

B4 CHECK FOR CORRECT BCM (Body Control Module) OPERATION

- Disconnect all the BCM (Body Control Module) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the BCM (Body Control Module) connectors and make sure they seat correctly.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new BCM (Body Control Module). TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.