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.
The Daytime Running Lights (DRL) are controlled by the Body Control Module (BCM). The BCM grounds circuit No. 592 in order to energize the DRL relay coil. This action places both low and high beam headlights (only high beams on Oldsmobile) in series with each other with the DRL relay terminal No. 87 providing ground and the RH HDLP fuse providing battery positive voltage. The BCM monitors the low beam circuit No. 1201 and high beam circuit No. 1200 to ensure that the DRLs are operating properly. If the BCM senses that the DRLs are not operating properly, DTC B2600 is set.