New here and need help!

Hey guys. I need help with my 89 Ford Taurus.

The story is:

I took the car in to a shop because wiring in the vehicle's charging system was damaged when I had major transmission work done. On Thursday, I showed up to the shop I was having repair the damaged wiring (because I know I can get in over my head too eaisly with electrical system problems). So, I pay $355, and when I get in the car I have no power whatsoever.

The service manager sees me getting under the hood, and he basically swaps the battery out and sends me on my way. I went to the gym, had the car parked for maybe 90 minutes max, and the battery was already dead. I got lucky that the car turned over very slowly with a jump box hooked up to it. I drove home, and of course there was absoutely no power whatsoever after sitting for a few hours.

I know there is one master relay in these cars that controls the A/C clutch and some other things and that relay can fail and put a pretty bad drain on the battery...is that what happened in my case?

So basically I have a short so bad it will take a full charge off a battery in just a few hours. Where should I look? Should I try and take the car back to the shop? Should I just swap out this master relay and charge ther battery and see if that helps anything? What can I do at this point?

I'm surprised you're even asking about it, to be honest, but I'm in the UK and maybe you do things differently over there. If I'd just paid all that money for an electrical repair and then immediately found myself with a non-functioning electrical system, I'd be taking it straight back to have them fix it.

You should disconnect the battery negative terminal overnight to stop it from draining the battery any further than it already is, and put the battery on charge overnight, if you have a charger.

As for swapping out master relays and such - well I can't comment because I don't know the model but I don't see that there's any onus on you to fix anything - there's plenty of onus on the repair shop to put it back together in proper working order though - that's what you already paid them for.

Having said that, if you find yourself in the position of having to fix it yourself then I'm sure you'll get plenty of assistance here. What do you have available in the way of test gear? Do you have a multimeter, or if not then do you have a 12V test lamp?

Something else which you have to consider is this: If the vehicle had been in good working order and then developed a fault, well you'd at least stand a fair chance of diagnosing it and making a successful repair. As it stands right now though, you simply don't know what you're dealing with - wires might have been transposed and might be connecting to places which they're not supposed to connect to, or not connecting to places which they are supposed to connect to, and you'll have no way of knowing if that's the case or not.

I'm an electronics engineer by profession so I'm comfortable around wiring circuits but even with my knowledge I wouldn't want to find myself in the position of having to work on that circuit. You'd need a good wiring diagram and you'd need to know the exact extent of the electrical work which was carried out at the repair shop, and even then it would be a daunting task.

Maybe I missed something, but why didn't the tranny shop fix the damage they did and why did you pay them before they fixed it? Selectron is an electrical engineer and no way I'd second guess him, but I believe you have a real wierd problem that is going to require a pro to fix it.

We help a lot of people here best we can but some problems, like yours, require a lot of knowledge and the advantage of hands-on testing which we can't do. Very sorry to hear of your delima and hope you find someone to fix it without costing an arm and a leg.