View Full Version : 98 audi a4 headlights won't work or reverse light

11-26-2014, 06:03 PM
My 98 audi a4 headlights stopped working.. both sides and only the low light orange lights will turn on or only the high beams when I hold it on.. also the sunroof randomly opens also if that makes a difference.. but I really don't know what the problem is with my headlights.. it can't be my bulbs.

11-26-2014, 07:50 PM
Looking at the wiring diagram, the headlight wires don't become common until they reach the switch. Your brights staying on when you hold the switch also points to a bad switch. Each individual bulb appears to have its own fuse, so all 4 would have to have blown simultaneously for them all to stop working, but check them anyway (fuses 18-21). The orange lights are on a separate circuit. I'm guessing 90% it's the switch. My sunroof switch is a bit quirky too, but it has never operated on its own at random.

11-26-2014, 09:07 PM
Your headlight problem is a common one to B5 platform. Leaving only the parking lights and "Flash To Pass" working. There are 2 possible causes, both are common failures:

1 - Headlamp switch failure (or sometimes the wire right at the switch connector)
2 - Ignition switch failure

In the case of #1, only headlamps are affected. Also, you can often clean the switch and restore it to working order (CLICK (http://www.audiworld.com/tech/elec114.shtml)). There are varying rates of success here, but a new switch is fairly expensive so might be worth a shot.
In the case of #2, other stuff will be broken. Specifically: wipers, radio, blower motor, etc.

The electrical circuit for the headlamps is not a complicated one by any means. A diagram and a test light (and perhaps some disassembly of interior covers) is all that it is needed to diagnose the issue - even without the above knowledge of the common failure items. Good Luck.