Circuit Description
WARNING: This page is about a different car, the 1999 Pontiac Grand Am and 1999 Oldsmobile Alero. However, it is still accessible from the selected car via links, so may be relevant.
This DTC indicates that a short to battery voltage condition exists in the ambient light sensor circuit. DTC B2648 will set if all of the following conditions occur:
- Automatic Lighting Control (ALC) is enabled.
- Ignition 1 is active.
- Ambient light sensor is shorted to battery voltage for 5 seconds.
When DTC sets, the check gauges chime will sound and the SERVICE VEHICLE SOON indicator will come on. BCM will go to sleep and wake up when DTC is repaired. DTC will clear from history after ignition switch is cycled on and off 100 times with no faults present. DTC can also be cleared using scan tool.