Amp Gauge Blow Up

[bliss]

Somehow, the Amp Gauge stopped working - battery issues surfaced and while checking all this out noticed that the wiring to the Amp Gauge and the Amp Gauge itself have been fried - some of the wiring practically melted together, some wiring ended up with no coating - only bare wire.

I'm surprise that there was no fire. I'm unclear as to what would cause this type of issue - anybody have any idea?

Anyway, re-wiring is necessary.

My question: What are the options at this point? Obviously one could replace the AMP Gauge and each wire, but is there wiring loom available from the Starter Solenoid?

My ERA was built in the late 80's so the wiring is old. It does generally follow the ERA wiring scenario, although the wiring pattern shows a link from the AMPS Gauge to the #1 Fuse Box - that Fuse Box has no fuse. Therefore, this is sort of a wiring Nightmare.

I'm officially not a happy ERA Cobra owner.

Input will be appreciated.

[patrickt]

You don't need to replace the burned wire, just snip it at both ends and run a new wire. The ammeter probably shorted out, via high resistance and too much current. That happens with ammeters and is why a lot of folks prefer voltmeters. The wire runs from the circuit breaker next to the starter solenoid over to the fuse box. I know you say it doesn't have a fuse in the #1 slot, but the hot side of the fuse is connected to the fuse below it. That's the charging path. If you look, you can see it. Just cut the wire at both ends, tape it off so it looks nice, and replace it with a straight shot of ten gauge wire from the circuit breaker to the #1 fuse position. Then you can just put a voltmeter in the dash. This is not a big deal.

[RICK LAKE]

Bliss, here's the problem, if you are running an Alt with 60amps or more and have a ampage draw with lights on, electric fuel pumps, blower for heater all running you are over the ampage the insolators on the amp gauge can handle and will melt. I went through the same thing and burnt the 2 wires and cooked the gauge. Do yourself a big favor. Replace the gauge with a voltage gauge from SW. It's black face and nobody will see the different unless you are looking for a 100% perfect cobra. Directly wire the 2 10gauge wires together and leave a pigtail to mount to the voltage gauge. You need a ground wire to the gauge and the light will pop into the new gauge. the new gauge also come with a light. Repair the other wires. I believe in the old days there was only a 37-42 amp charging system. Today we run from 60 to 100 amps depending on was acc you have in the car. I run a 95 amp system with dual fuel pumps, 3 cooling fans. 3 duct fans, ECU for FI system, power for the injectors, and other misc curcuits. Putting the same gauge back in the car will only over time cause the same failure. Make sure you either tape all the wires burnt, replace them or srink tube them and replaced the end connectors to get the tubing on. I used a heat gun at the low setting to get good melting and not damage coating on other wires. Good luck Rick L. After repair make sure the wiring doesn't get hot. You could have a short or rub at another location like behind the ALt. Make sure the Batt wire is not hitting or rubbing at or around the head area. Couple of guys have had this happen to their cars. I have a cover to protect this connection. God luck Rick L. Ps looking for another amp gauge, burnt and going cheap PS depending on how bad the wiring is and location, cut the harness taping back far enought to see good coating and replace wiring from there. Make sure depending on what connectors you use to solder the wire to the connectors. If you use butt connectors, get weather type ones and heat the ends to seal the connector. Also heat the center where the crimp is to melt the solder for a better connection. Don't let it catch on fire or melt the butt connector. Do you have a camera and could shot a couple of pictures to see the damage?? This would help with repairing it. This is not an ERA production failure, it's a gauge failure. Be happy it's not a total failure of the car as it melts to the ground. God was looking over you. Small easy repair. be happy could have been ALOT WORST. What number is your car?? I have 428. This was about the time Bob made some changes to the wiring system. I have an old wiring diagham on my car. I think the wires that burnt where white or yellow??We can fix it. Rick

[bliss]

Thanks Patrick.

[bliss]

Rick....(large pictures below)

It's ugly under there - especially now. Wires, other than those going directly to the AMPS Gauge were impacted - all the damage appears to be under the dash.

Yes, wires that burnt where white or yellow - but also a large black wire that comes directly from the AMPS Gauge (my brother informed me that that's a 'hot wire' - that's also the wire that ended up with no black coating at all (under the dash) - completely fried but it's OK on the firewall side.

Question - is a voltage gauge from SW wired in the same as an AMPS Gauge?

[patrickt]

Do you see how the left side of fuses #1 and #2 are joined together? Do you see the yellow and red wire both are soldered together on to the top screw to fuse #1? Yellow goes to the ignition switch and RED goes to the amp gauge (orange goes to the alternator). The red wire is what you want to snip along with the top lead to the circuit breaker. That red wire is fried up under the dash. This is really an easy fix, much easier than you think. And a voltmeter is just a simple two wire run.

[DanEC]

Bliss - it's of little consolation but in all probability it's nothing ERA had any control over. Amp gages are just a risky deal. If you have been around awhile you may remember all those Mopars back in the 60s and 70s with the wavering amp gage in the standard dash. They ran all of the alternator current through that cheap gage and Mopar dash fires as a result have always been a problem. Throw a "Smiths" gage into the equation and now I'm kicking myself as to why I didn't have ERA substitute a voltmeter in my dash.

Unfortunately your burnt wiring is quite a bit worse than the one I had recently when my alternator connection wire got loose. I think you will at least have to pull the harness out enough to unwrap it sufficiently to inspect all wires next to the burnt one for damage.

If you can isolate which wires need replacing either due to being fried by the alternator gage and having the insulation fried by heat, ERA can fabricate just those wires for you and then you can place them in the harness and re-wrap it. Or an all new front harness is always an option.

I agree - it's a bummer.

[patrickt]

The purple wire looks a little dicey.... But I can't tell if that purple wire runs to an unused dead end or if it runs off to something else.

[Hotfingrs]

The first thing I did when I bought my ERA was replace the amp gauge with a volt meter. With all the accessories running through it, it's an accident waiting happen. Hopefully fixing your wiring won't be much of a problem. Last year I also had my whole car rewired and now have a box on the firewall with blade fuses.

[RICK LAKE]

Bliss I had the same problem. I also see in the picture and I think it's the speedo cable, wires rubbing on the top. Unscrew cable and get wires run below cable. If you can smooth out the loop in the cable than would help to and expend the life of it.
Easiest way to fix this is a razor knife and open up the wiring harness. You may want to remove the windshield and steer column from the car for easy way to repair this. Sound like a pain but all you have to do is flip the dash 90 degrees to repair. Work 1 wire at a time. Remove and splice in a new one. Solder the ends and seal them. Some of the better auto stores have bulk wire in different colors. Try and match gauge thickness and color if possible. Match the Gauge wire if nothing else. Larger the wire the more amps it has to carry. Trailer stores also have wiring in bulk, Like house or boat trailers. If not Electrical outlets. When done with the repair, leave the dash loose to see behind and run the car. You can do this by hand or with a infrared temp gun and watch and check for hot wires. They will be easy to touch. Run the car about 5-10 minutes if no smoke or hot wires show, put the car back togeather. I like wireties and use less tape. Weather will not hurt the wiring under the dash if it gets wet.
Volt gauge, very easy to do, The 2 main wires that would have gone back to the amp gauge now are connected together with large crimping connector or just replace the 2 wires, (which is better since you have the dash loose) and add new ends to where they go. For the gauge just add a wire split into the large wire. Everybody has a different way to do this, here's mine, Get a 1" piece of 16 gauge wire, match the color if possible. this tells you or a mechanic it's a power all the time line. I pull back just enough of the wire cover to patch the wire in. I use an awl to push though the wires and make a hole. Strip the match wire about 1" and run this through the hole and wrap it around the main wire. Nice spot of soldered for good contact. They sell liquid plastic wire sealer in electric at Lowes and homedepot. Put a couple of light coats on the connection. Tape over if you want too. Better than new.
Install gauge. Cut the pigtail to length and add eyelet to end of wire. Use the liquid seal or tape or swrink tubing to protect for wire rub, and kepts out weather from corriding the connector. The instructions tell you which terminal the line goes to. Next find a ground wire. They are black most of the time. You need a test light or ohm meter to check this. Once you find a good ground wire run a pigtail of black 16 gauge to the other side of the meter. Light explains itself and should just clip in. If it's a different socket than splice in the new one to the light feed. Take your time. There must be a couple of guys in the area that would help you with this. Normally a couple of beers and a steak will win over any good guy. NO driving after the beer. If you have a problem, stop and call, Will walk you through this. Rick L. 732-254-3536 Home after 7:00 pm est time. Good luck . Sorry a voltgauge and amp gauge are not wired the same. All the power of your electrical system go through the amp gauge. Over time the load and heat melt the insolator on the amp gauge and you get smoked. Voltage gauge just samples the amount of power your charging system and draws use and the number is whats left over with th car running. It's also a quick battery tester. Turn Ign switch to on and you can see the voltage of the battery.

[patrickt]

Bliss, Rick's idea of flipping the dash down is a good one. It's just six screws around the perimeter of the dash and it tilts right down. That will give you easy access to the wiring. A job like this is always much worse in your mind than it is once you've actually started working on it. Dropping the dash, 10 minutes; inspecting the wires, 15 minutes; running a new straight shot of 10 gauge between the fuse box and the circuit breaker (right along the engine side of the firewall, no need for it to go back under the dash), 20 minutes; repairing one or two slightly toasted wires, 15 minutes; installing a new voltmeter, 20 minutes; button it all back up and check for misplaced tools left under the dash, 10 minutes. See? Rick could easily have it all done in less than two hours (I could easily spend all day on it). This is not a hard job and it will be difficult for you to break anything new while you're doing it.

[lippy]

I replaced the ammeter with a voltmeter before I ever got the car on the road. The ammeter is essentially a big exposed welder in your dash, and I didn't want to risk the trouble. Too much current running through it. BTW, ERA has directions for a voltmeter swap, and they are different depending which vintage ERA you have. If you do want to replace it, speak with Bob at ERA and he will point you in the right direction. It's not hard.

[bliss]

Originally Posted by Hotfingrs

The first thing I did when I bought my ERA was replace the amp gauge with a volt meter. With all the accessories running through it, it's an accident waiting happen. Hopefully fixing your wiring won't be much of a problem. Last year I also had my whole car rewired and now have a box on the firewall with blade fuses.

Last year I also had my whole car rewired and now have a box on the firewall with blade fuses.

What's the ballpark cost of a complete whole care re-wiring?

I have ERA 091, so everything in the wiring area is really old and a little strange in many ways. The original owner appears to have changed things around so I'm ended up with wires that are cut off, capped off and going nowhere. It's, frankly, a little scary.

[DanEC]

Originally Posted by lippy

I replaced the ammeter with a voltmeter before I ever got the car on the road. The ammeter is essentially a big exposed welder in your dash, and I didn't want to risk the trouble. Too much current running through it. BTW, ERA has directions for a voltmeter swap, and they are different depending which vintage ERA you have. If you do want to replace it, speak with Bob at ERA and he will point you in the right direction. It's not hard.

Lippy - do you have a picture of your dash - I would be curious to see what the voltmeter looks like versus the amp gage. I'm guessing it's a 90 deg reading gage also?

[bliss]

Originally Posted by patrickt

Do you see how the left side of fuses #1 and #2 are joined together? Do you see the yellow and red wire both are soldered together on to the top screw to fuse #1? Yellow goes to the ignition switch and RED goes to the amp gauge (orange goes to the alternator). The red wire is what you want to snip along with the top lead to the circuit breaker. That red wire is fried up under the dash. This is really an easy fix, much easier than you think. And a voltmeter is just a simple two wire run.

Here's my fuse block set-up - as you can see, very old and a little scary looking to me. Notice that there isn't a fuse on the left side, first slot. The Cobra ran fine with no fuse in that slot - everything seemed to look OK.

[patrickt]

That "empty" fuse usually runs the fan. Your fan must be wired in and fused elsewhere. But look over on the left side and you can see that the hot sides of fuse one and fuse two are connected. That's the charging path. All THREE of those labeled wires are connected together. It also kind of looks like the connector between fuse one and fuse two looks a little melted, but maybe not. The red wire is the one that should run to your ammeter and from your ammeter to the circuit breaker, that is the last stop before the battery. The other two wires I have labeled for you. Now, I could always be wrong on this so check the actual wiring. You can look under the dash at the ignition switch pretty easily, and of course look at the alternator. You can replace that red wire that caused all the problems without having to actually remove it. Just cut it at both ends (fuse box and circuit breaker) and cut it out from under the dash as best you can, then tape it all off. When you drop the dash you'll be able see how that red wire goes to the ammeter. When it heated up, it may have damaged some other wires as well, but you'll be able to see that. If it looks really, really bad to you, then just send it up to ERA and they'll do it for you. But I think that if you replace that red wire, with a straight shot between the circuit breaker and fuse box, and then touch up any scorched wires under the dash, and put in a volt meter, you'll be fine.

[patrickt]

You can see why the prior owner pulled the fan fuse and, I'm guessing, ran a direct fused connection directly to the fan. There is evidence of heat damage from the fuse blowing, probably more than once, and he kept upping the amperage and it kept blowing. What is that little black necklace looking thing? Is it some kind of insulation buffer? And is the apparent melting on the connector between fuse 1 and fuse 2 just an optical illusion? I've never seen that guy even pucker before, much less melt. I'm guessing it's just a trick of the camera.

[bliss]

Originally Posted by Hotfingrs

The first thing I did when I bought my ERA was replace the amp gauge with a volt meter. With all the accessories running through it, it's an accident waiting happen. Hopefully fixing your wiring won't be much of a problem. Last year I also had my whole car rewired and now have a box on the firewall with blade fuses.

OK, I'm sold on a voltmeter, so Summit (for example) has 20 SW voltmeters - is there a specific one that works well in an ERA?

[patrickt]

Originally Posted by bliss

OK, I'm sold on a voltmeter, so Summit (for example) has 20 SW voltmeters - is there a specific one that works well in an ERA?

Just so long as it fits the existing hole in your dash and you like the way it looks. Voltmeters are all the same.

[bliss]

Originally Posted by patrickt

You can see why the prior owner pulled the fan fuse and, I'm guessing, ran a direct fused connection directly to the fan. There is evidence of heat damage from the fuse blowing, probably more than once, and he kept upping the amperage and it kept blowing. What is that little black necklace looking thing? Is it some kind of insulation buffer? And is the apparent melting on the connector between fuse 1 and fuse 2 just an optical illusion? I've never seen that guy even pucker before, much less melt. I'm guessing it's just a trick of the camera.

Black Necklace...
A closer look - it's some sort of crud that has built up on the end of the wire clip - looks a little baked on to me - probably tape, etc.

Between 1 and 2 fuse...
Looks like someone scraped something off.

I'm wondering if I should consider starting over - new harnesses, etc.