Jim Grant's Tech Tips
'96 Chevy Cavalier, No Left Side High Beam
Q: I have a Ď96 Chevy Cavalier and my right high beam is not working thus resultingin my Daytime Running Lights (DRLs) not working. The low beams work fine whenturned on. I have measured voltage in the high beam light and it is around 3volts, low beam has 12+ both sides. If I splice power together a foot back fromthe headlamp assembly everything works fine. I am assuming that the splice isbad causing a lot of resistance and dropping current. I have back probed wireto the other side of the vehicle but I can't find where the splice is. Do youhappen to know where the common power splices into two separate feeds? This wouldthen allow me to track the issue.
A: When you say right high beam are you talking about the driverís side headlight as you look at the vehicle? If that is the case you may have a problem with the DRL module/relay. The driver’s side high beam receives its power through a relay contact inside of the DRL module/relay. When the high beam quits just on the driver’s side and the DRL stops working it is a good bet that the DRL module/relay has a problem. So before you start cutting up your wiring harness looking for splice problem, I suggest you look closely at the fuse for the driver’s side head light and then at the DRL module.