98 Cadillac Deville Concours

[ryanusrey2012]

hi i have a 98 Cadillac Deville Concours and the low beams do not work yet all the fuses are intact is this a ground problem or a security feature i am still figuring this car out and the highbeams still work but when i turn them off the runners are the only one to work and also one headlight is broken but the one that is not defective does not work

[Tony Silva]

I don't think it will be a ground problem as the Hi-Beams share the same ground wire. It could be that for some reason the wire(s) going to the low beams has no power going to it. Check the plug socket to see if it has power going to it. If it does then replace the bulbs. If there is no power You will have to probe the wire for the lights with a test light to find the bad section.

[gmtech1]

There is a high/low beam relay in the underhood fuse box you can check also.

[ryanusrey2012]

my relays look fine and so do the fuses. could the daytime running light module be causing this because they do not come on only the parking lamps do. also i heard on newer vehicles if a bulb goes out the computer will stop sending power to the defective lights untill the computer is resetted any ideas?

[ryanusrey2012]

could it be the dimmer switch? thats what the dealer told me but they always want you to buy all their parts to and they just said dimmer switch with no logic behind it

[maxwedge]

A shop manual with a circuit tracing diagram is the only way to properly diagnose this or there will be a lots guess work in the repair process. BTW, relays can't look okay they must be tested or substitued