Help please...Dart swinger elictrical problems.

[hpgs]

I recently inherited a 70 dodge dart swinger with a 340 4 speed. It has been converted to electronic ignition and some other aftermarket stuff done such as a 30 amp fuse added in on the fire wall. The problem started at a car show, it drove great to the show but when I went to leave I turned the key and nothing. The fuse that was added on the fire wall was blown so changed it and the car fired right up. Drove a few hundred feet and it blew again. Put a new fuse in then a crank no start problem. With some testing found out the electronic ignition module was faulty so I replaced that. Now the car will run but the gauges other then the volt gauge don't work and the left signal lights stopped working along with the interior dome light. I checked the fuses under the dash and they have power on both sides of all fuses.I am new to these cars and looking for any advise on where I should start looking for the problem. Sorry for the long winded post.

 

[dano]

Go here and download the free manual for your car, keep in mind this covers Charger and Coronet so pay attention in the wiring diagrams for "Dart".

Service Manuals – MyMopar

For now and while you gather testing information disconnect the battery. The addition of the 30 Amp fuse tells me there is something the previous owner did or issue they knew about.

Your car, if stock, has an Amp meter and did it ever work? It is common for people to bypass it.

Basically your going to have to figure out what's been done and what is not stock. How good are you with a voltmeter?

FYI those Mopar ignition boxes need to be case grounded.

 

[hpgs]

Go here and download the free manual for your car, keep in mind this covers Charger and Coronet so pay attention in the wiring diagrams for "Dart".

Service Manuals – MyMopar

For now and while you gather testing information disconnect the battery. The addition of the 30 Amp fuse tells me there is something the previous owner did or issue they knew about.

Your car, if stock, has an Amp meter and did it ever work? It is common for people to bypass it.

Basically your going to have to figure out what's been done and what is not stock. How good are you with a voltmeter?

FYI those Mopar ignition boxes need to be case grounded.

It was my uncles car it is stock except the electronic ignition and that fuse. I installed the ignition box the same as the previous one it is bolted to the inner fender. I am not the greatest with a volt meter

 

[H22A4]

Electrical issues can be challenging but this could be a great opportunity to become familiar with a volt meter and understanding circuit basics (ie: grounds, wire tracing, etc) that will help you many years down the road!

While it might be stock, 50+ yrs later they rarely are stock. While your uncle might have only said he touched the ignition and added a fuse, something tells me he probably did a few more things.

 

[hpgs]

From what he remembers the fuse on the outside was added because he kept blowing fuses in the car

 

[H22A4]

The fact he added a 30A fuse to avoid blowing fuses under the dash only masked the problem!

Best download the electrical diagrams for your year Dart (link provided by another member already in this thread) and start problem solving. It will take some time but it will be worth it once you find the problem.

 

[67Dart273]

Hacked wiring is always tough because the rest of us have no idea what was done. One "popular" mistake is to blow the fuse link, and then replace that with a fuse. A 30A fuse is almost never enough, because even the lowly 37A alternator can sometimes blow that. All you need, EG, is some rain and cold, need heat and wipers, headlights, the battery a bit low needing charge, and now you have the alternator working hard at full output. And the fuse heats, and engine heat will also affect the amperage at which either a fuse or breaker pops, and then you have zip
FIRST thing I would do, as advised, get the manual, post back as you go, and figure out in what circuit was the added fuse placed.

Then I would pick one part of the problem and troubleshoot that as if it were one problem, and go from there. I guess I would work on the turn signal problem first, and or the dome light and try to pick it second.


One thing that might have happened is that some fault or a faulty VR may have caused the alternator to greatly overcharge/ over voltage and may have popped some bulbs. Hard to say about the gauges. That would be one explanation as to a suddenly bad ignition box.

 

[dano]

Case in point, the wiring in my car is a nice dull brown instead of shinny copper. Places where the jackets are molded have pulled away. A month ago I about burned the dash because the "Brake" light harness grounded out to the dash frame when I was working on my custom dash. 6" of wire went up in smoke before I got to the switch. I've fixed countless poor repairs by previous owners. After these issue I plan to rewire the car this winter. Age, sketchy ownership, materials of the era all add up to needing to check all the wires for safety. As you noticed there are like 4 or 5 fuses and not all circuits are fused.

If you plan to keep the car all original there are company's that make new harnesses if you find a bad one and need to replace it.

 

[Mattax]

It was my uncles car it is stock except the electronic ignition and that fuse. I installed the ignition box the same as the previous one it is bolted to the inner fender. I am not the greatest with a volt meter

Doesn't seem stock. Your car did not come with a voltmeter. it came with an ammeter. The reason the factory used a fusible link was to allow more than 30 amps briefly. A 30 amps spike is OK. 25 amps for an hour is not so great.

Probably the best thing to do is look at other simialr cars, and then make up a diagram showing what has been done to this car.Good news is that your may remember more when you point to things and ask about them.

 

[str12-340]

can you provide a picture of the wiring at the firewall with the 30 amp fuse. Folks are making assumptions about what it is. a picture of the bulkhead connector that shows which wire is fused will clear that up. Your car is 55 years old (like my 70 Darts). The designers never thought your car would exist after 20 years let alone driving around at 55!

You can spend a LOT of time patching the mess of 55 years worth of jack leg repairs, or you can replace the whole wiring system with a factory correct set of wiring harnesses, replace compromised components that the wiring plugs into and have a dependable, traceable system that should be good for another 30 years. M&H makes dead on factory replacement wiring for your car from the head lights to the tail lights.

If you choose to patch things up, buy a good Halon fire extinguisher so at least you don't burn up the whole car...

 

[Mattax]

Here's the basic scheme.

The battery wire A1 only has current flowing through it during start up and recharge.
The ammeter shows 40 amps discharge to 40 amps charge. Generally the battery should charge at less than 10 amps. And should be fully recharged (0 amps) after a few minutes.
Starting sequence illustrated here.

How the starter relay works.

Current Flow with battery recharging immediately after start

 

[hpgs]

Hey guys update on the issues my altrantor was severely overcharging. It took out the voltage regulator, ignition module, voltage regulator for the gauges and most of the exterior bulbs in the car. I have everything working again except the tac and now with thegauges they will work for a brief second then go back to the position when there is now power and then they will just keep doing that. Looking for ideas on things to look at next.