High current draw burnin out battery wire

Hi guys, I have a problem with my car. I'm from the uk so its a british car. Its a 1988 Ford Orion. My problem is that one of the wires connected to the battery has melted due to the heat generated from a high drain. The wire gets really hot when running with instruments on like the heater etc. This particular wire seems to run the entire car's electrics as when the wire got disconnected once when i was driving, the whole car died and stalled. Any ideas as to what would cause the high drain and how i should repair it? Heres a picture of the wire i have taken, don't worry about all the other wires comin from it as they are just for the alarm and the amps in the back of the car. Cheers.

fireballuk2001 wrote: My problem is that one of the wires connected to the battery has melted due to the heat generated from a high drain.

Is this the factory (OEM) positive battery harness that is showing signs of being burnt? If that is the case, then the current load is too high.

fireballuk2001 wrote: The wire gets really hot when running with instruments on like the heater etc. This particular wire seems to run the entire car's electrics as when the wire got disconnected once when i was driving, the whole car died and stalled.

The way you discribe this wire harness, would lead me to believe it is the vehicles primary power supply. But understand this, even if you were to disconnect the batteries positive lead, the alternator would keep the vehicle running. So, if the vehicle did die due to one of these wires this would indicate that your charging system is faulty.

fireballuk2001 wrote: don't worry about all the other wires comin from it as they are just for the alarm and the amps in the back of the car.

The wires are not fused... That is a fire hazard, and a accident waiting to happen.. I would suggest a fused power distribution block in future upgrades this vehicle may encounter. Regards EVIL Teken . . .

Yes it is the factory OEM harness that is showing the burnt wire. I also half agree about the charging system as it certainly does make sence that the alternator should've taken over, however if the wire is supplying power to the ignition circuit, and its possible that the alternator isnt, it would have cut out too. The picture does not show this, but all the wires connected to this positive terminal for the alarm and the amplifiers have inline fuses connected to them further down the cables.

fireballuk2001 wrote: Yes it is the factory OEM harness that is showing the burnt wire.

Well, based on your reply. The first thing you should be aware of is that the current positive battery harness MUST be replaced. As it is now, the primary wire harness, has been damaged and will never flow the same amount of current as it did when it was new. You do not need to replace it with the exact same harness, but realize that the outer sheath / insulator is very thick for a reason and standard power cable is not. You may use any variety of welders cable, which is so rated and insulated to provide the current needs you require. You would of course install the largest guage wire you could afford.

fireballuk2001 wrote: however if the wire is supplying power to the ignition circuit, and its possible that the alternator isnt, it would have cut out too.

The vehicle only relies on the alternator / generator to supply the power it requires to operate while running. The battery is there only for (4) reasons. 1. To start the vehicle. (primary reason) 2. To supply back up current, when the alternator cannot under hi-current loads, or about to fail. 3. To provide a measure of electrical absorbtion of rectification faults. 4. To supply current / power for standby accessories such as the ECU, clock, alarm, etc

fireballuk2001 wrote: The picture does not show this, but all the wires connected to this positive terminal for the alarm and the amplifiers have inline fuses connected to them further down the cables.

This is good to hear.. The welfare of you, and those you love are the primary goal at all times. Regards EVIL Teken . . .

Ok, i'll see if i can get it replaced soon with some high guage wire. I've been told by someone that the other wire may be the trickle wire back from the alternator. I can't see that myself as im sure the wire goes to the starter motor and then to the battery and is of a high guage wire... however if my friend was correct, that would explain the cut out of the car. Oh and thankyou for the reply and the kind words, your right about loved ones being the primary goal in life :o) Not so EVIL Teken after all eh ;o) Cheers

my sisters ford thunderbird did the same thing - and it didn't keep running either - reason:  there was a short somewhere else in the wiring harness, which was pulling more current than the alternator could supply AND keep the electronic ignition and fuel injection systems going while idling.  since you don't apparenlty have a 6 foot long melted wire, i'd assume your problem was similiar to the one on her car was - someone who had replaced the battery had chaffed a couple of the larger wires and they were shorting out on the body (of course, they would do it where you couldn't see it until there was smoke starting to billow out of seemingly nowhere)  if you simply can't seem to track your short down by any other means, find a cheap compass, then set it near the wiring, and connect your battery and disconnect it.  keep watching the deflection - when you finally get to a point where it's not deflecting the compass anymore, then you've passed up where the short is, go back.