69 rs
I put in new trim rings and headlamps and decided to clean up the voltage regulator and horn relay too. Put everything back together and now there's no headlights. I put a tester on the three prong connector pulled off the lamp and no power anywhere. The parking lights and blinkers and inside dimmer work fine and Ive never had any trouble with the old lights, but decided to put new ones in when I replaced the trim rings. Im pretty sure I put all the wires back right. On the horn relay, the driver side tab has a red and black thick wire and the pass. side has two thick black wires. All the voltage regulator wires can only go one way so those are probably right too. Im not really an electrician so thought Id see if anyone has run into this problem and knows more about getting power to the headlamps. I was wondering if I could have put something together wrong. I have the grounds to rad support on tight on unpainted metal. Basically, I get power to the parking lights at the plug but not to the headlamp plug and I dont know what to check next.

Might want to check fuse in fuse block.

I looked but didnt see any fuse related to the headlamps on the fuse panel. I have instrument lights blinkers and parking lights working but no power to headlights. Is there a special fuse for the headlights only?

When you took your measurement, what did you use for ground? It looks like the 16 gauge tan wire is pwr to the headlamps. Pull the plug off the lamp again and check that wire to a good gnd with the lamp sw pulled all the way out. Ya I check my fuse panel and didn't see anything labeled headlamp but check the one labeled tail fuse 20A. If you have your meter handy, I would ohm out.

I would also take a quick reading on the thick red wire on the horn relay to ground. It should have 12v on it. If not, you took out the fusible link usually located behind the battery going to the junction blk. on the firewall.

I just my checked my horn relay and unless an RS is different than non RS, mine is hooked up with the thick red and thick black mounted closer to radiator and a thinner black and green mounted closer to driver fender. This is with the wires coming out of the bottom. There is also a pink wire for the key buzzer in there too. The thick blk and red are actually tied together by the horn relay. It's just acting as a junction block.

thanks for the post. I have no pwr to the headlamp connectors but all other lights work fine including tail lights. On my horn relay, I put a thick red wire and a thick black wire on the driver side tab on the horn relay. On the pass side I have two other thick wires that are black. Maybe this is wrong? I dont get why every other light is working perfectly but no headlights or power to headlamp connector when pulled off. The fuses all look fine and if my tail lamp works I would guess the tail fuse is ok. It does look ok. Im thinking maybe I put the horn relay wires together incorrectly. Car starts ok so everything is ok except the headlights, and theyre new, but get no power.??

added: I checked some pics in the forums and my wiring seems to be ok, but no pwr to headlights. Grounds seem ok as I put a test light on the headlamp ground wires and touched to a hot wire and it lit up.

After looking at prints, the headlamp circuit is it's own monster. Again, not sure about an RS, but that 12ga Red wire coming off horn relay goes to the light sw. pin 1. The light sw shows an internal breaker. From there pwr comes out blue wire pin 6 to high beam dimmer sw on floor. (Might try depressing sw to see if maybe its stuck between positions. From there tan wire up to headlamps.

Did you disconnect battery when you were working on the horn relay? Any sparks noticed? Did you check voltage on the thick red wire?
Here's a pic of my horn relay.

http://i55.photobucket.com/albums/g136/Caman355/MVC-001F-29.jpg

Thats a nice firewall you have! Well, I decided to go through the grounds and checked the floor switch after. The blue, and tan and high beam green wires. After tightening and inspecting every ground on the car almost I went to the switch with the tester. Everything had power at the floor dimmer. I had a feeling the weak ground was fixed and the lights would be shining in the front...THEY WERE ! lol, I guess it was a ground but I dont know which was the culprit. Thanks for the help and the pics. I also found some good ones in old forums. Those new headlights sure look pretty all lit up lol! It really helped when you mentioned the foot switch in your last post. Thats a great check on the current for the headlights.

Awesome!! Way to go. Grounds will do it every time. Usually 75% of problems are grounds.
Enjoy your new lights.