Circuit/System Testing

WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.

Hood Ajar Switch Circuit Malfunction

Ignition OFF, disconnect the harness connector at the hood ajar switch.
Test for less than 10 ohms of resistance between the ground circuit terminal B and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
Connect the harness connector at the hood ajar switch. Disconnect the X1 harness connector at the BCM.
Ignition ON, verify a test lamp does not illuminate between the signal circuit terminal 26 and ground.
- If the test lamp illuminates, test the signal circuit for a short to voltage.
Ignition OFF, hood closed, test for 700-800 ohms of resistance between the signal circuit terminal 26 and ground.
- If not within the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the hood ajar switch.
Hood ajar, test for 6K-8K ohms of resistance between the signal circuit terminal 26 and ground.
- If not within the specified range, test or replace the hood ajar switch.
If all circuits test normal, replace the BCM.