So long time reader first time poster here... I've done some searching yes I know how to use the search feature...
OK randomly when I start my 99 alero GLS at night only at night my SVS light kicks on and my parking lights and my interior dash lights don't come on. I can turn them on with the switch and they work fine
Sounds like a funky relay...I agree....now watch it be something like the exhaust is 2 decibels to loud...its always something crazy.
Hope you find out whats going on.
It sounds to me like it's the sensor on the dash for the night time lights. Mine did that, thew a code, and had the identical symptoms. I replaced the sensor and everything was peachy again!
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Ahhhhh!!!!!! Don't Scratch My Paint!!!!
Sounds like the relay to me, too...since it's only doing it at night. The sensor is telling the computer it's dark, computer commands the DRL relay on, and nothing happens. Boom...code.