Can anyone tell me why all of a sudden my headlights are surging. Just started doing this recently. Kinda looks like some of the motorcycles going down the road the way the lights pulsates. Any ideas. Thanks in advance.
Sounds like a short, time to start playing with the wiring, start at the socket and work your way back, if they are getting brighter with higher rpm's it is probably the alt.
Alt is what I thought about first. As far as the gauge jumping I didn't pay that much attention to it.
just curious , does it do this only after cold start - No it was when I got out of town and away from the street lights on a dark road that was when it was easy to see.
Just check alt 15 minutes ago. After GPR cycle it puts out 14.48 volts. Checked out both batts just before checking alt. Had no reason to go anywhere today so even after both batteries have been sitting since lastnight, when I first noticed the surging. Both were sitting at 12.44 volts.
I believe there is a relay feeding your headlights. Depending on the year it might be under the steering column with the fuses. If it is, your owners manual will list which bay it is in. I would try swapping it with an identical relay from another bay and see if that cures it.
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