At my wit's end!

Gotta love that wiring . . .
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richfolsom

At my wit's end!

Post by richfolsom »

OK, so I've been trying to get my passenger taillight as well as dash lights to work for some time now with no success. I also have a drain on the battery.

I'm now to the point where I want to take it in, does anyone have any recommendations of somewhere in the Austin, TX area that could look at it?
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divace73
Posts: 1380
Joined: Sun Oct 17, 2010 5:59 am
Your car is a: 1980 Fiat 124 Spider Silver
Location: Sydney, Australia

Re: At my wit's end!

Post by divace73 »

you will need a multi meter and set it on current and run it in series (inline from the negative side of the battery to the chassis (making sure the negative cable is disconected and the meter is continuing the path))
Then pull out 1 fuse at a time taking note on what current is drawn.
You may also have some grounding issues (which may be causing the problem to start off with)
You'll need the wiring diagram for you model and trace where the grounds are and ensure they are clean.
Hope this helps
Cheers David
-=1980 silver Fiat 124 Spider=-
If you want to see pics of my car (and other random stuff) >>click here<< OR
see my >>You tube channel<<
dmwhiteoak
Posts: 1088
Joined: Mon Aug 15, 2011 1:12 pm
Your car is a: 1972 Fiat 124 spider
Location: White Oak Tx

Re: At my wit's end!

Post by dmwhiteoak »

I think I saw you there yesterday. I also was at Witt 's end last night, left it about 9 when I decided to go in the house. I hit a bump in the road and blew a fuse. 10+ fuses later I got it home and started isolating the different components fed from the J fuse. Somehow the door chime was what was blowing the fuse. Once I cut the power to it I blew no ore fuses. But now my headlights will not come on. Go figure. These grimlins are very frustrating you just have to get a diagram and stay at it. Brad Artige has diagrams posted and if someone would be nice enough to lead us to them I think we both could knock these electrical grimlins in the head :mrgreen: Good luck and keep us posted.
Dennis Modisette

1972 124 Spider
2003 Chevrolet Z71
2007 GMC Yucon
TX82FIAT
Posts: 1814
Joined: Mon May 03, 2010 11:04 am
Your car is a: 82 Fiat Spider 2000 CSO
Location: San Antonio

Re: At my wit's end!

Post by TX82FIAT »

Guys, below is the link to Artigue's web space. Stick with it. 90% of the problems are related to grounds, connection points and fuses. These wiring diagrams are a big big help when tracing a circuit that is not working. The electrical gremlins in this car are all about patience and systematically working through each circuit. It took me two weeks to trace down a short to ground that was blowing fuses in the blink of en eye. Hit a bump and it shifted what looked to be a piece of copper wire like those used on a metal clothes hangar that was pushed through the wiring bundle under the dash to help keep it secure to the metal rail. The metal wire and a frayed wire that rubbed against it over time created a short to ground. Who pushed a copper wire through a wire bundle to secure it! In any event, I'm not sure a mechanic would have been willing to pull the dash off a 30 year old car to trace continuity in a circuit. If a mechanic is willing to go into that type of depth you are going to pay and arm and a leg defeating the purpose. Again, most of the time it is something basic that just takes time to find. Stick with it.

http://www.artigue.com/fiat/
Buon giro a tutti! - enjoy the ride!

82 Fiat Spider 2000
03 BMW M3
07 Chevy Suburban
richfolsom

Re: At my wit's end!

Post by richfolsom »

OK, here's the latest. I was able to get everything working like before. I had blown a fuse, and didn't notice it. Now, I'm back to square 1. The passenger side tail light doesn't work. All of the others (blinker, backup, brake) work fine on the passenger side. I was playing around with the ground that comes out of the driver side circuit board and here's what I found. If I completely unscrewed it, the driver tail light still works. However, the fuel pump doesn't work, and the driver tail light dims when the turn signal is on. Also, all of the lights come on very dimly on both sides when the key is in the on position, even the tail light and license plate lights. Any ideas?
So Cal Mark

Re: At my wit's end!

Post by So Cal Mark »

the fuel pump grounds to the light mounting stud, dimming lights with increased load indicates a bad ground. Those circuit boards are notorious for corrosion issues
richfolsom

Re: At my wit's end!

Post by richfolsom »

yeah, that's what's weird about it. If I unscrew that ground completely, that's when I get the dimming lights. but the lights still stay on, like it's grounding through the fuel pump line somewhere else. When everything's plugged in, I don't see the dimming lights. I bought some cleaner, that's my next plan of action, to make sure the board is all clean and the connections are good.
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SLOSpider
Posts: 1140
Joined: Wed Mar 03, 2010 2:10 am
Your car is a: 1973 124 Spider 2.0FI
Location: Lompoc, Ca USA

Re: At my wit's end!

Post by SLOSpider »

Do this and report back. Take a jumper wire and run it from the negative battery post to the ground post on the right tail light and see what happens. Sounds like it just has a poor ground. I use a long piece of wire with alligator clips to help diagnose ground and power problems.

Yesterday I was removing and cleaning both tail lights. When I put back together everything worked at first then the left turn light was constant on and no tail light. While I was leaning my chest against the rear bumper and my arms across the trunk I could actually feel electricity in my chest area, although slight. Like sticking your tonged on a weak 9v battery. So I knew it was trying to ground somewhere. I used my jumper wire from battery to the tail light stud and lights started working again. The ground wires on the rear lights are very poor requiring a good body ground at the light housing. I am going to redo this and have a new grounding location to the body for the lights to ground to. It also does not help when everything was repainted and have no more good metal to ground to. I used some sandpaper to sand away the paint on the body where the ground wire, washer an nut go and reconnected.
1975 124 Spider
1976 Mazda Cosmo http://www.mazdacosmo.com
1989 Chevy k5 Blazer
1967 GT Mustang Fastback
richfolsom

Re: At my wit's end!

Post by richfolsom »

ok, now for the embarrassing news. Somehow I didn't realize that there's a different fuse for each taillight, so I ruled out it being a fuse issue. After studying the wiring diagrams more closely, I did notice there were two fuses, and after inspecting one of them, I realized that it was blown. After replacing it, it works fine.

Now after putting everything back together, I somehow screwed up the turn signals and one of the reverse lights. I think the reverse light should be easy, no idea about the turn signals. I do know the first thing I will do is check the fuses though.

Thanks everyone for your responses and help, and I hope someday to be able to pay it forward to someone else when they're fighting with fiat electronics.
User avatar
SLOSpider
Posts: 1140
Joined: Wed Mar 03, 2010 2:10 am
Your car is a: 1973 124 Spider 2.0FI
Location: Lompoc, Ca USA

Re: At my wit's end!

Post by SLOSpider »

turn signal make sure key is on and check the ground as stated. Reverse light may also be the ground but also check the bulb if its just one side that is not working. Also need to have hazard switch is plugged in for turn signals.
1975 124 Spider
1976 Mazda Cosmo http://www.mazdacosmo.com
1989 Chevy k5 Blazer
1967 GT Mustang Fastback
vandor
Posts: 3996
Joined: Sat May 23, 2009 1:23 pm
Your car is a: 1971 124 Spider
Location: Texas, USA

Re: At my wit's end!

Post by vandor »

Hey,

Do you know about the Fiat meet in Buda this weekend?
Email me for info.
Csaba
'71 124 Spider, much modified
'17 124 Abarth, silver
http://italiancarclub.com/csaba/
Co-owner of the best dang Fiat parts place in town
richfolsom

Re: At my wit's end!

Post by richfolsom »

You guys are the best! I had forgotten I unplugged the hazards. everything is working great now.
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SLOSpider
Posts: 1140
Joined: Wed Mar 03, 2010 2:10 am
Your car is a: 1973 124 Spider 2.0FI
Location: Lompoc, Ca USA

Re: At my wit's end!

Post by SLOSpider »

Great! good to hear.
1975 124 Spider
1976 Mazda Cosmo http://www.mazdacosmo.com
1989 Chevy k5 Blazer
1967 GT Mustang Fastback
richfolsom

Re: At my wit's end!

Post by richfolsom »

ok, got everything working again. we found out that the passenger reverse light was wired totally wrong. after redoing that, it was all good. Now I'm only down to some sort of mysterious battery leak, then a bunch of cosmetic stuff. It's getting interesting now. :D
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divace73
Posts: 1380
Joined: Sun Oct 17, 2010 5:59 am
Your car is a: 1980 Fiat 124 Spider Silver
Location: Sydney, Australia

Re: At my wit's end!

Post by divace73 »

richfolsom wrote:ok, got everything working again. we found out that the passenger reverse light was wired totally wrong. after redoing that, it was all good. Now I'm only down to some sort of mysterious battery leak, then a bunch of cosmetic stuff. It's getting interesting now. :D
with battery leak, do you mean electrical or the acid?
Cheers David
-=1980 silver Fiat 124 Spider=-
If you want to see pics of my car (and other random stuff) >>click here<< OR
see my >>You tube channel<<
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