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So, recently had headers installed and the shop did a fine exhaust job but somewhat sloppy reinstalling-everything-else job. F ex they mixed up spark plug wires etc and I had a little headache getting things right.
A couple of days ago, after fixing the ignition (spark wires), I went for a drive and suddenly after 10 minutes of driving things got dark. Dash lights went out, headlights went out and tail lights went out. Luckily I was 1 km from home. I could close the headlight hatches but after that they don't move.
The 20A ctsy fuse had melted but a new one didnt fix anything. Could it be the button, on the dash?
Hazard and turn signal works (at a slightly higher speed), fan works, gauges work etc but no lights. Not the hatch motors and not the light.
Any tips on what to look for, besides the button?
(Car is a 91 GTA)
Re: Head-, tail and dash lights died while driving
The shop should be held accountable, if you didn't have these issues before they should fix it.
With that said I would check the fusible links at the starter for damage, kind of makes sense since they would be working close to this area installing headers
Have you checked all of your fuses with a multimeter for continuity? You've got issues with circuits that are fed from different sources
Re: Head-, tail and dash lights died while driving
Thanks. I got an apology but its impossible for me to prove anything is related to the installation until i figure out what's wrong, and i have driven 50-60 km since then. Most of them on five cylinders, haha.
I'm thinking some wires might be too close to the header tubes, insulation melting and shorting out. But.....what wires even go there, on the lower part of the firewall?
Will check all fuses!
Re: Head-, tail and dash lights died while driving
Originally Posted by Andreas_91GTA
Thanks. I got an apology but its impossible for me to prove anything is related to the installation until i figure out what's wrong, and i have driven 50-60 km since then. Most of them on five cylinders, haha.
I'm thinking some wires might be too close to the header tubes, insulation melting and shorting out. But.....what wires even go there, on the lower part of the firewall?
Will check all fuses!
It's possible that the wiring at the starter could of accidentally been compromised during the install, installing headers on these cars aren't exactly the easiest thing to do.
Were you saying the head light motors weren't working as well?
Re: Head-, tail and dash lights died while driving
Originally Posted by 91banditt2
It's possible that the wiring at the starter could of accidentally been compromised during the install, installing headers on these cars aren't exactly the easiest thing to do.
Were you saying the head light motors weren't working as well?
Correct. I could shut the head light hatches (via the head light/parking light switch) when everything went dark but cannot get them up again.
Re: Head-, tail and dash lights died while driving
Originally Posted by 91banditt2
What about your fog lights, are they working?
Are your interior lights working? Dome light, Map light, radio, cigarette lighter?
Dome light is dead.
Cig lighter dead (doesnt pop back up)Radio works
Brake lights workService engine, parking etc on the dash works
The mystery continues...
Re: Head-, tail and dash lights died while driving
Originally Posted by Andreas_91GTA
Dome light is dead.
Cig lighter dead (doesnt pop back up)Radio works
Brake lights workService engine, parking etc on the dash works
The mystery continues...
Re: Head-, tail and dash lights died while driving
Checking the fuse box. It was actually the 20A tail light fuse which not only went but plain burned up!
Thinking something completly shorted out. Does the wiring to the tail lights ever go near the exhaust?
BBQ One row down from top of photo, third fuse from the left
Re: Head-, tail and dash lights died while driving
As I said before you've got issues across multiple circuits.
If it were me I'd start with....
A visual inspection of the of the fusible links at the starter
Check to see if you have 12vdc on the red and orange wire at the light switch, red wire is going to one of those fusible links and the orange wire will be coming from the tail light fuse, these should be energized with key on or off.
Check all of your fuses with a multimeter for continuity especially the ACC and TAIL fuse, the ACC fuse powers the interior lights and the TAIL fuse supplies power to the headlight switch.
Re: Head-, tail and dash lights died while driving
Originally Posted by Andreas_91GTA
Checking the fuse box. It was actually the 20A tail light fuse which not only went but plain burned up!
Thinking something completly shorted out. Does the wiring to the tail lights ever go near the exhaust?
BBQ One row down from top of photo, third fuse from the left
That's not a normal reaction to over current for a fuse, I'm wondering if they grounded out the positive side of the starter solenoid with a wrench, it would make sense that a 20 amp fuse would blown before a fusible link as those are rated for 30 amps (I think?)
Re: Head-, tail and dash lights died while driving
So, the link was at the battery oh, well... Replaced it but still no progress. Guessing the switch is the problem but will continue following the main wires through the car.
Re: Head-, tail and dash lights died while driving
Will remove passenger side headers, just to be sure nothing has melted under them. New dash lightswitch will be here on friday.
Will also probably remove the stereo/radio. Don't use it anyway.
Re: Head-, tail and dash lights died while driving
Originally Posted by Andreas_91GTA
So, the link was at the battery oh, well... Replaced it but still no progress. Guessing the switch is the problem but will continue following the main wires through the car.
Re: Head-, tail and dash lights died while driving
Originally Posted by 91banditt2
So a fusible link was bad?
Didn't measure it and it wasn't burned off. However the press joints was really crusty and I replaced it all with mini fuse sockets, just for peace of mind. Measuring from + at the battery I got a beep from the multimeter touching the passenger side headers when reaching for the starter.. Could be a glitch as it only happened once bit cant help thinking something (bare wire) is way to close to the headers under there.
Also one ground braid from passenger head to firewall was dangling completely loose.
Car still starts an runs fine. Ctsy, head and tail lights still dead. Also replaced every fuse under the dash and found some wrong numbers in the sockets.
Kinda enjoy replacing old wiring and making stuff new.
Re: Head-, tail and dash lights died while driving
Took the passenger side headers off and replaced all wires at the starter.
So:
New fuses everywhere
Replaced fuseable links with 30A fuses in sockets.
New wires
Still dark. That leaves the switch, which will be here on Friday. If that doesn't solve it im out of ideas. Tonight I'll take the dash off (I think).
Last edited by Andreas_91GTA; Nov 17, 2022 at 06:35 AM.
Re: Head-, tail and dash lights died while driving
Old switch seems fine. It shorts like it should. Will remove cig. lighter and stereo. Reading about c100 connector and will locate it tomorrow. I'm getting 22,7 % frustrated.....
Re: Head-, tail and dash lights died while driving
Originally Posted by Andreas_91GTA
Old switch seems fine. It shorts like it should. Will remove cig. lighter and stereo. Reading about c100 connector and will locate it tomorrow. I'm getting 22,7 % frustrated.....
The C100 is located on the driver side firewall, standing in front of the engine compartment it’s to the left of the master cylinder, there’s likely a group of relays above it http://www.austinthirdgen.org/mkport..._1992_C100.gif
Re: Head-, tail and dash lights died while driving
Will dig into the fat harness down by the drivers side frame, next to the headers. Can't help thinking all this was caused by heat. Had no issues with anything until headers was installed.
Located the c100 connector but my hands were frozen.....
A warm garage and car lift is on my christmas list
Re: Head-, tail and dash lights died while driving
What's the point of taking + from the starter? Why not directly (and fused) from the battery?
Because they are one and the same thing; just, at opposite ends of a REALLY THICK piece of wire, aka battery cable.
But the starter is a MUCH friendlier place to hook a wire to, since it's a big threaded post that you can just keep adding ring terminals onto if you want. A binding post one might say. Whereas, there's no real good place to hook additional wires up to, at the batt itself. And the starter post is away from the battery acid and all that besides.
If you have no power getting to C100, then the problem is between that post on the starter, and C100. There's only 2 things there: a fusible link, and about a 6' piece of #10 or #12 (I forget) wire. One of the 2 Big Red Wires that feed EVERYTHING inside the car.
Re: Head-, tail and dash lights died while driving
Originally Posted by sofakingdom
Because they are one and the same thing; just, at opposite ends of a REALLY THICK piece of wire, aka battery cable.
But the starter is a MUCH friendlier place to hook a wire to, since it's a big threaded post that you can just keep adding ring terminals onto if you want. A binding post one might say. Whereas, there's no real good place to hook additional wires up to, at the batt itself. And the starter post is away from the battery acid and all that besides.
If you have no power getting to C100, then the problem is between that post on the starter, and C100. There's only 2 things there: a fusible link, and about a 6' piece of #10 or #12 (I forget) wire. One of the 2 Big Red Wires that feed EVERYTHING inside the car.
Check the fusible links at the starter.
And today it started snowing. Managed to poke around for an hour before my fingers went numb
I replaced the fuseable links earlier this week but nothing changed. I think I will move them to the battery and start testing them, finding one by one (if possible). I had three links on my car where one was spliced into two continuing to the harness.
I have no power at the light switch, ignintion on or off. Everything is dead. Will look into the power distributor block if something is up in there.
It really starts to get on my nerves. Think I have spent 20 hours trying to find the problem...... but I'm confident I eventually will and then I'll laugh at my stupidity.
Re: Head-, tail and dash lights died while driving
I think I will move them to the battery
Don't.
No advantage to doing that. Won't fix a damn thing except by raw unadulterated unvarnished unalloyed ACCIDENT. Just makes a mess and requires splicing or whatever, and brings you no closer to finding the problem.
FIND THE PROBLEM and don't just f*** with the wiring for the halibut.
Trace every point you can get to with your DMM looking for 12V. As you go along, each time you find 12V, move to the nextr point. Whenever you come across wherever it disappears, check over everything between this point and the last point VERY CAREFULLY. You'll find it; instinct tells me it'll be OBVIOUS. Burnt wiring, corroded connector, and so forth.
Re: Head-, tail and dash lights died while driving
Originally Posted by sofakingdom
Don't.
No advantage to doing that. Won't fix a damn thing except by raw unadulterated unvarnished unalloyed ACCIDENT. Just makes a mess and requires splicing or whatever, and brings you no closer to finding the problem.
FIND THE PROBLEM and don't just f*** with the wiring for the halibut.
Trace every point you can get to with your DMM looking for 12V. As you go along, each time you find 12V, move to the nextr point. Whenever you come across wherever it disappears, check over everything between this point and the last point VERY CAREFULLY. You'll find it; instinct tells me it'll be OBVIOUS. Burnt wiring, corroded connector, and so forth.
DON'T f*** with the wiring. Just REPAIR it.
It will be much simpler checking the wiring if I know which fuseable link is broken, if any. I'm not talking about permanent installation by the battery. And since I replaced them all they should be good.
Following the red wires through the harness (behind plastic tubing) will be great fun.
It might be a coincidence it broke down just after installing headers.
Re: Head-, tail and dash lights died while driving
Ever since "High Amperage" Fuses (Maxi, Mega, ANL, Etc) became available, I have stopped using Fusible-Links.
The majority of the Fusible-Links are located at the Starter-Motor Battery Stud...
So that they are in a somewhat safe location for the Link to Break/ Burn-up.
A bad enough Draw or Short to Ground will cause the Fusible-Link to burn and at times actually catch fire briefly.
Fuel Lines, other Wiring Harnesses, and anything else that could potentially cause a Flaming Fusible-Link to continue to burn and cause a real fire...
Should not be anywhere near Fusible-Links.
When I install new Harnesses in our Cars (Street Car or Motorsports Spec.) the Fusible-Links are the very first thing to go in the trash!
Re: Head-, tail and dash lights died while driving
Finally!! FI-NAL-LY!!!
I have spent 50+ hours in rain, snow and -2 degrees celsius with frozen fingers. I have probably been a PITA at home, always thinking of what went wrong with the d@mn car. I have checked fuseable links twice (and dismounting passenger side headers), checked every ground, made new ground cables, new connectors, cleaning all grounding surfaces, taking apart half of the interior and dash looking for ground points. I have measured cables a thousand times for broken connection while laying on my back on the drivers seat with my head by the fuse box, dismounted the stereo and generally poking at everything more times than I can remember.....and suddenly a red wire by C100 in a presumeably home made bundle came loose. It was a press jointed, shrink wrapped and strapped little bundle I have looked at several times and FINALLY something happened. When I saw it I felt so happy my hands were shaking and I almost failed making a new 30A fused cable, haha.
What an adventure! I think I will celebrate with a Fitech TPI
oh, well... Replaced it but still no progress. Guessing the switch is the problem but will continue following the main wires through the car. 
