'99 Grand Am GT "service vehicle soon" warning light on, DRL fault?

'99 GA GT, H.O. V6, A/T, 97,2xx mi.
The "SERVICE VEHICLE SOON" light is on, not to be confused with the "SERVICE ENGINE SOON" light....
Just did mega-service to this car, now this....
According to the owner's manual, it indicates a fault in the DRL/ALC system.
When started, in Park, at night, headlights off, all the exterior lights come on except for the headlights. "S.V.S." light comes on with chime about 5-10 seconds after started. Headlights come on as usual with switch.
There's a tip on disabling the DRL/ALC in this forum, but I just want to repair it. Does anyone know what causes this failure? Is there a relay or underhood fuse that could be at fault? Is this something that needs be scanned at AutoZone or something?


Thanks!

That's something easier: replace your headlights!

DRL put both headlights on high, and in series, which give half the voltage to each. if one fail, both turn off.

You can confirm it by putting your headlights on high beam. One will not turn on.

D'oh!! Didn't even think to check that, I automatically assumed it was a more sinister problem. :smokin:
Thanks Phantom!!