The daytime running lights (DRL) system is comprised of
the following components:
| • | The body control module (BCM) |
The following conditions must be present to allow the DRLs to illuminate:
| • | The ignition must be on. |
| • | The park brake must be unapplied. |
| • | The transaxle must be in any position except PARK. |
When the above conditions are met, the BCM will supply ground to the
DRL relay placing both headlamps in series with each other. Battery
voltage for the DRL relay is supplied through the HTR-A/C IGN fuse. When the
DRL relay is energized, ground is supplied to terminal B (A-Oldsmobile)
of the left headlamp instead of battery positive voltage through CKT 150
and CKT 593 (refer to
Headlights Circuit Description
for a description of normal headlights operation.
Battery positive voltage for the DRLs is supplied through the RH HDLP fuse
(CKT 640) to terminal B (A-Oldsmobile) of the right headlamp.
With ground at terminal B (A-Oldsmobile) of the left headlamp and battery
positive voltage at terminal B (A-Oldsmobile) of the right headlamp,
both headlamps will illuminate at a reduced intensity compared to normal headlamp
operation.
