Headlights wont work

[e30Prestige]

Hey guys,
So i replaced a few tach bulbs yesterday and realized that after the install I suddenly had no headlights or fog lights. The parking lights come on and the tail lights come on.
The easiest thought is that the fuses are blown or the relay is bad. I'm pretty sure it's not the switch itself because the parking lights and rear tails still operate.

Anyone have any thoughts?

[e30Prestige]

replaced fuses still nothing. trying relays next

[spdracrm3]

check the connector on the back of the light switch for being bumped or pulled loose as you worked on the cluster , the light switch controls the ground side of the K4 lowbeam and K8 foglamp relays so its possible the ground G200 under left side of dash above brake pedal is loose or pulled off also

[e30Prestige]

ok so I checked the wires in the back of the switch and everything looks fine. This leads me to my next interesting discovery.

I decided to change the low beam relay just to rule that out. I pulled the old relay and popped the new one in and finally had headlights and foglights... with the headlight switch in the off position...
So i turned the lights on and the headlights turned off and the parking lots came on...
So now i'm more confused. If it was a loose wire somewhere would the headlights even come on at all even with my little relay trick? I swapped a few relays around and it looks like the relay that came out of the low beam headlight position is definitely bad because it doesn't power the high beams when i tried it there.

I'm hoping someone can swoop in and offer me some advice and at the very least explain why my headlight switch is playing opposites with my parking lights.

[e30Prestige]

also dont have cluster bulbs when I turn on the headlight switch. Had 1 bulb that was good before and now that I replaced the 3 main bulbs nothing works.

[spdracrm3]

check and make sure you are using the correct relay ,there are different pin orientations on the relays and you may have put a different one in (the pins are numbered when flipped over 85,86, 30,87

[e30Prestige]

thanks I'll check that

[e30Prestige]

Alright some more interesting discoveries. Found out my cluster bulbs do work as I originally thought they didnt. However, still no headlights when the switch is on. Ordered a new bmw switch and installed it with the same results.

I have found that with the headlight switch off the headlights are on. With the switched pulled in once, the parking lights come on. With the switch all the way out nothing more happens. I also noticed that when the fog light button is in the on position the fog lights come on and when turned off the headlights AND the fog lights turn off. I can then operate the fogs paired with the headlights with the fog switch.

This car has me pretty much smashing my head against concrete around every turn. All of this was sparked by a simple cluster bulb replacement and a steering wheel swap (mtech 1)

[e30Prestige]

Is there anything in the back of the instrument cluster that could cause the headlights not to come on if there happened to be a lose wire?

[spdracrm3]

wow this is a strange one for sure ,im still leaning to something being pulled loose somehow when you were working on the cluster . just doesnt make sense that the headlights come on when operating the fog switch unless something has been modified in the wiring (i wonder if someone tried to do a foglight only conversion on this car and that is backfeeding the system somehow) the wiring for both headlight (switch to K4 ) and fog lights switch to K3 pass thru the C103 29pin connector at pin 11 and 14 respectively i would be looking at that connector and also since you change the steering wheel check the c202 combination switch connector .

this wasnt a canadian car was it? they had a DRL conversion up there that changes everything see this lengthy post which we came to a resolution on for a similar issue http://www.e30tech.com/forum/showthread.php?t=119183

do you have a test light and DVOM and how comfortable are you at using such?