Diagnostic Aids
WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.
- If the DTC B2647 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
- The following conditions may cause an intermittent malfunction to occur:
- An intermittent short to ground or a short to battery positive voltage in the signal circuit of the DRL ambient light sensor.
- An intermittent short to ground in the low reference circuit of the DRL ambient light sensor.
- An intermittent internal short to ground in the ambient light sensor.
- An intermittent internal short to ground in the BCM.