Glazedham42

iTrader: (4)

Hey guys,

I'm having some wiring trouble with my car, and I'm pretty sure that I fried my fusible links on accident. I looked through several of the threads in the archive and I replaced my fusible links with a fuse box out of a 2nd Gen.

I thought my fusible link was toast, because when I was working on my hazard/headlight combo switch I accidentally crossed the red and black wires that I think go to the hazard switch. As you can imagine I got quite a few sparks, but there was also a considerable amount of smoke coming from under the dash, and around the driver's side inner fender. I blew several of the fuses in my fuse box when this happened, so I immediately replaced all of those. Everything seems to be working ok now, except for my headlights.

I can't get the headlights to illuminate fully on normal or brights. I was also having trouble with my headlight motors but after swapping in the 2nd gen fuse box, the motors are ok. When I turn the headlights on the filament in the lights barely glows. I checked the wiring at the bulb harness and I am getting 12 volts there. I don’t understand why the bulb won’t fully illuminate though. Also, when I turn the brights on, I get nothing. The filament in the headlight doesn’t even glow. I wonder if I accidentally burnt up the switch that controls the headlights? It doesn’t really make sense to me though, because the headlights go up and down perfectly when I turn the lights on, they just don’t illuminate. Also my turn signals work just fine too. But for some reason I’m not getting enough juice at the bulbs to make them illuminate beyond a little glow.

I looked through my Haynes and it mentions two more fusible links underneath the steering column. Should I open up the cover and check those two links? It just doesn’t make sense to my why I’m getting a little bit of electricity but not enough to fully illuminate the lights. To me if I blew out a fuse or a link, it should be an all or nothing type situation. If anyone has any suggestions or ideas to try PLEASE LET ME KNOW! I’m not the best when it comes to wiring….

Thanks in advance fellas!

Jamie

lovintha7

Volts aren't what you want. Check how many amps your getting. If that's fine, change a headlight and see if it's bright. Most likely you fried the filaments in the light with that massive jolt.

Glazedham42

iTrader: (4)

These are brand new headlights that I have in the car right now. They weren't even installed when I fried the car, so they couldn't possibly be damaged. Sorry, should've clarified that from the beginning. I will try and check how many amps I am getting through the wiring connectors. It can't be much at all, because the filaments in those headlights were barely glowing....

Until I can get an exact amperage tomorrw, does anyone have any more ideas of what would cause this to happen?

Rogue_Wulff

Check the ground as well. A poor ground will cause the lights to be dim.

Tech_Greek

Screw all that,

My lights would do the same thing because of the multi-function switch, if you didn't hit it just right it would be DIM lights.

All in all, check the volts in the cockpit on the steering column. My dad just recently went through the same on his new old RX7, the lights didnt even work because all the wires melted so we re-wired it and the lights wouldnt still go up and down and come to find out it was because of the switch.

- Tech

Glazedham42

iTrader: (4)

So what do you do to fix the switch inside? Can I rewire it, or am I going to have to completely replace it?

JKM

You can try to take the switch apart and clean all the gunk out of the insides. I don't honestly think that's your problem, but it wouldn't hurt. Just be careful when taking it apart, there are some tiny springs and ball bearings that like to jump out and get lost. And don't break the turn cancel thingie getting the wheel back on.

I'm having a similar problem but haven't been able to post due to proxy errors. I don't have the dimming problem, but I have no brights at all. The low beams are fine, and pulling back on the switch to flick it works fine. If anyone has any solutions, I'm all ears.

LongDuck

Most likely, when you fried the wiring in your multi-function switch (headlight control column), it allowed enough current to flow such that it melted some wiring together under the dash, or maybe in the steering column extension. When you try to turn the headlights on, the motors are controlled through the Fusible Links at the driver's strut tower, but the current that makes the headlights 'bright' runs through a relay located under the dash. If your wiring has melted together somewhere along the line to that relay, you're shorting out the relay control or otherwise bleeding off current to a ground somewhere - that's not good. You need to find that.

I would start with the wiring that you were working on and trace it back up and under the dash - you're looking for any wiring that is melted, so feeling your way along the wires should help you find some that are stuck together, indicating a place that they may be shorting. Find this short and splice the original wiring back together, or wrap with electrical tape to ensure that they can't short out, and you'll probably be fine.

Check your Haynes manual or FSM (better) for a Headlight Relay in the engine bay, and it may be worth replacing that first if you have a spare - much faster, and could fix your problem. HTH,

Oh, yeah - don't connect red and black wires together anymore. Also, don't ever remove your shift boot cover. There are two connectors under there that fit together, but if you connect them, you will cause any number of electrical problems - don't do it.

Glazedham42

iTrader: (4)

Longduck,

Thanks for taking an interest in the thread. I've noticed around here that you are extremely helpful to the -SE guys, but seeing as I have an '85 GS I haven't ever been able to take advantage of your knowledge. What you are saying makes perfect sense to me, and I even wondered if there was a relay somewhere for the headlights, or headlight switch.

Just to clear things up, I didn't intentionally connect the black and red wires on the hazard/headlight combo switch. My post makes it sound like this is what I was trying to do. What happened was, as I was fighting with my gauge cluster I bumped the two wires and they came in contact with one another. Scared the crap out of me, sent sparks everywhere, and saw some smoke coming from under the dash and near my fusible links under the hood. I'm still not positive that it was the fusible links smoking, but I replaced them and the headlight motors are functioning again, so I'm pretty sure I toasted them. Whether or not they were causing the smoke I don't know.

The thing that doesn't make much sense to me is, the wires that I crossed go into the harness for the hazard/headlight combo switch on the dash. I don't see how that electrical surge could get all the way back to the multifunction switch for the lights on my steering column. Wouldn't the damage have to be on the other side of the relay? My thinking is that everything on the "multifunction switch side" of the relay would be fine, because the relay would blow out before any real damage was done to the switch itself on the steering column. I hope this makes sense. I realize that electricity can be unpredictable at times, so I really shouldn't rule anything out.

Does anyone know if there is a relay for the headlights, and/or multifunction switch on an 85 GS? If so where is it? Thanks for all the help so far felllas!

Jamie

LongDuck

Well, here's some more info straight from the 85SE FSM:

NO HEADLIGHTS LIGHT
Fusible Link Blown - replace
Faulty combination switch - Check
Faulty wiring or ground - Check

(admittedly, not much help...)

Running through the circuit diagram, I'm not sure there's actually a relay that powers the headlights, as it would appear that the current runs straight from the battery to Fusible Links to the combo switch and back out via RL and RY (Red wires with Yellow stripe and Red wires with Blue stripe).

The FSM goes on to have you remove the headlight connector from the back of the lamp and check voltage/amperage (which it sounds like you've done). If the voltage is different than battery current, there may be a malfunction of the headlights or a bad grounding connection. Still not much help from the FSM on this.

I would start back at the combo switch and have a good look at the Red/Yellow and Red/Blue wires coming from this to the rest of the harness. Usually the Fusible Links will blow very quickly if you send 12v through them in a dead short, but it sounds like they carried enough current to burn something else up. Since you mentioned the smoke coming from under the hood, check your wiring harness leading to the front of the car for the headlights as one of these may have burned up also. Did you check the bulbs? It's usually the simple things. HTH, keep at it,

Glazedham42

iTrader: (4)

Ok, I've been playing around a little bit with some stuff and I've got more info that may or may not shed some light on the problem. First off, the actual headlights are brand new, so it can't be them. They weren't installed in the car when the power surge occurred. I even tried a spare headlight I had to be sure. It did the same thing. So its not the headlights.

Second, and more importantly, when I unplug a wiring harness from one of the headlights and leave the other one plugged in, the one that remains plugged in becomes brighter. I may be wrong, but even if I unplug one of my headlights, the remaining headlight should maintain a constant brightness, correct? I didn't think that they were supposed to act in this manner, but I could be wrong. Could some wiring have melted together to cause this to happen?

Finally, I've been doing some visual checks on the wiring of the car, but I'm not really sure what I"m looking for. If the wiring is damaged, is it something that is going to be visually obvious to me when I see it? As many of you know, the underside of the dash is an absolute mess of wiring, so I'm having a tough time even trying to decide what to focus on. Should I just untape the main harness in the engine bay and look it over? Any advice on inspecting my wiring would be appreciated. I'm not sure how to go about it....

Thanks guys. I'm still clueless here, but I feel like I'm on the right track...

Jamie

Glazedham42

iTrader: (4)

Ok, I'm getting very close here I think. I went out for a while and did some prodding around on the car and figured out a little more. I turned both of the lights on like normal, from inside the car, and then grounded one of the headlights right to the battery. Both of them brightened right up, and the brights work great as well. So, for some reason my headlights aren't getting a good ground at the headlight harness. So I guess my next step would be to trace the ground wire from the harness and see where it ends up? Is there any reason why I can't just trace it down and then replace it? I just want to make sure I'm not leaving some kind of a short somewhere that might cause a fire later. But for now it seems that my only problem was the headlight ground....

I'll keep you guys posted on the fix. Hopefully this thread might help someone else in the future...

Kentetsu

Here is a link to Daniel Stern's page;

http://www.danielsternlighting.com/t...ys/relays.html

I followed their intructions to upgrade the entire lighting circuit and I highly recommend it for anyone who owns a 7. The stock wiring for the lights is as wimpy as can be, and it all runs right through the switch and back to the lights, without the use of any relays. A very poorly designed system, and totally inadequate.

The difference in lighting power after I upgraded everything to 10ga wire w/relays was incredible. I ended up having to re-aim my lights a little bit due to people flashing me with their brights. Much, much better than stock in my opinion.

JKM

Does anyone know which color the wire is that comes out of the back of the multiswitch that controls the high beams? I've fiddled with mine a bit, and I'm pretty sure it's the wiring now and not the switch, but I'm not sure which of the billion wires I need to follow...