Topic: Battery/Alternator

[73Formula]

Since my brake issues have just been fixed, a new problem has developed.    My car use to run showing 15 on the battery gauge. Now it has dropped down to the yellow/red zone, 10 or 11. It did this gradually, I assume that the battery is not getting charged when teh car is running. (I have non-original gauges) Would that be the alternator not charging or the battery going bad or both? The headlights started to get dim and my window would not roll up, I had to "help"it. Thank God I was in my driveway.
thanks
KC

[RENOVATIONS]

Easiest way to find out for sure is to go to a parts store and get them both checked....most will check them for free

[73Formula]

Cool, thanks will prolly go tomorrow.

[brian c]

IF you're in the market for a battery, might I suggest a yellow top from Autozone? They have a better warranty than the Sears Diehard brand and are cheaper. I run one in my TA - its currently sitting in the basement on a battery tender for the winter. The one I bought has both top and side posts. I prefer the top posts because of the number of add-ons I run.

I will be doing the same thing for the Tundra when that battery gives up the ghost.

[Rarebird]

Oh the delima of this.. LOL... if your worried about the car not making it to the nearest auto parts store here is a few simple test to get you started... start the car and let it warm up of course... while the engine is running take a screwdriver and place it on the back of the alternator bearing cover. you should feel a slight magnetic pull on the screwdriver tip IF the alternator is charging properly. Since the car has started in the past I would most likely say its the alternator... another simple test is also while the car is running to remove the positive battery post ( being careful not to allow it to touch metal)... if the alternator is defective the engine should die(shut off) since the battery is disconnected and the coil is recieveing power from the alternator only.

[73Formula]

This car is cursed- noticed the alt belt was a little loose, but decided to pull the alt and the bat anyway to get them checked out. They both are fine, put it all back together, make sure the belt is not loose, car starts and pulls 14 -15 volts- Great fixed it right? wrong. WRONG. Drive it out of the driveway and down the street, the needle was making little dips now and then, which I assumed was the belt slipping. Turned a corner the car died instantly and smoke came out from under the hood. Looks like my whole engine harness fried! Piss on this, Im gonna take this car to TA of Florida and make it their problem for a while, when they have space available.

[Kevin]

This car is cursed- noticed the alt belt was a little loose, but decided to pull the alt and the bat anyway to get them checked out. They both are fine, put it all back together, make sure the belt is not loose, car starts and pulls 14 -15 volts- Great fixed it right? wrong. WRONG. Drive it out of the driveway and down the street, the needle was making little dips now and then, which I assumed was the belt slipping. Turned a corner the car died instantly and smoke came out from under the hood. Looks like my whole engine harness fried! Piss on this, Im gonna take this car to TA of Florida and make it their problem for a while, when they have space available.

Have the alternator and battery tested and save yourself some money. I worked at Autozone over the summer before I left for college and they will test alternators and batteries for free there. If your alternator is bad, I recommend getting a higher output one online if you plan on running an aftermarket stereo etc, but if not just get a new one from autozone. The batteries they sell are really good. They come with a 3 year free replacement warranty with two years of pro rated warranty for 5 years total. They'll install it for free (if you don't mind them touching your car) and they are far better than the diehards or the interstate batteries. We replaced more interstate batteries than any other as I recall.

If you replace the alternator and battery or whichever wasn't working then you're going to need to check into the harness. It's really not that bad. I was new to the wiring stuff and really scared to do it myself but Brian and others on here helped me through it.

Save yourself some cash and have the alternator and battery tested before you put it into an expensive specialty shop to do pretty simple work you can do at home.

Kevin


EDIT

Just saw you had your battery and alternator checked. Next step is to check through your harness for any burnt wires. Check the wire that runs from the alternator to the battery and the engine harness as a whole. If you are going to need a new harness, you can get a new one from M and H electrical for a good price. I replaced the engine and forward lamp harnesses in mine with pieces they supplied and it was really quite straightforward. Take some pictures and ask more questions if you need to before you take it to the shop because chances are, this is something that can easily be fixed.

[73Formula]

Thanks for the advice- the wire had burn marks all the way through, looked like a total system melt-down. I would be inclined to do as you say and do it myself, teh problem is that under the hood it is a nightmare- alt is on the wrong side, wires everywhere, smells of gas etc. Its a real Mickey Mouse disaster under there. I would rather have it put RIGHT and then start doing things myself. How often does the wire harness go bad? Im assuming that was my original problem since my alt and bat were fine. Do you recall how much a harness was? Could there be ANOTHER existing prob that caused the harness to go bad?
Thanks
KC

[Kevin]

Thanks for the advice- the wire had burn marks all the way through, looked like a total system melt-down. I would be inclined to do as you say and do it myself, teh problem is that under the hood it is a nightmare- alt is on the wrong side, wires everywhere, smells of gas etc. Its a real Mickey Mouse disaster under there. I would rather have it put RIGHT and then start doing things myself. How often does the wire harness go bad? Im assuming that was my original problem since my alt and bat were fine. Do you recall how much a harness was? Could there be ANOTHER existing prob that caused the harness to go bad?
Thanks
KC

I've done this before but Brian is better than me. For the time being, I'll try to lend my advice.

The engine harness starts at the firewall on the drivers side where it is coupled to the fuseblock with the forward lamp harness. It runs out from there with wires going to the distributor, the starter (purple wire I believe) and of course there are a few wires that run to your alternator you only need two hooked up I believe. There's one that plugs into the side of it and is "plug like" and there's a ring terminal type that hooks onto the BAT pole of the alternator. From that Bat terminal, you should have a cable running from there to the positive post of the battery that provides the juice or charge. You should also have a green wire that goes to the temperature sending unit in the manifold of your motor. That's about all I can remember off the top of my head as I am 5 hours away from my car at college. The harness I believe cost me like $165 and it's a perfect match to the factory original in every way. You tell them your engine, your year and it's perfect.

Their customer support is top notch and they WILL walk you through the installation not to mention the help we can offer you here.


As for your current situation check for burnt wires, check for shorts and check your grounds. If you're convinced your current harness is bad which it seems it might be then a replacement is in order. I've got a feeling that a wire grounded itself out and shorted the harness out. If the wire has a chaffed area with exposed wires next to metal then that's your answer right there.

If you need help just ask. I'm away from my car, but I can hopefully still help from memory plus Brian is the man when it comes to this stuff.

[brian c]

From your description it sounds like you had a massive short. This would be a bare wire touching a good ground. Considering your car is 30+ years old and was probably still using the original harness I'd wager that some of the insulation wore off and started arching.

All that is moot though as you currently have a fried harness (or two). Here's what I would do:

M&H Wiring harness - forward light harness & Engine harness.

Here's why: The forward light harness & the engine harness bolt together as an assembly to your fuse block on the firewall. Since you're already there you might as well save yourself a step and replace both at the same time. They're both the same vintage and may have suffered the same fate.

Now its really easy to replace both harnesses. There's just (1) bolt under the brake booster that holds both wiring harnesses to the fuse block. Now the bad part - in order to replace these, the best bet is to unbolt your driver's side inner fender and roll it out of the way so you can actually reach the bolt.

As for wire colors and destinations:

*Purple wire with ring terminal - starter solenoid
*Pink wire with white connector - BAT connection on your Distributor
*Blue wire with white connector - oil pressure sending unit
*Green wire with white connector - temp sending unit
*Red wire with ring terminal - goes to your ALT terminal
*Brown & Red (I THINK this is it anyways) in a 2 prong connector - plugs into your ALT

There's a few more wires in the engine harness itself. Those go to your wiper motor assembly.

The forward light harness is very straight forward - it will only go in one way and you can't mess it up. Trust me. I'd never done it before and between the engine and forward light harness I think I had them swapped out in an hour. I'm no mechanic - I'm an IT guy.

**I'm doing all the wiring colors from memory and its been a while since I've done this so my suggestion would be to grab a piece of paper, note where your current engine harness plugs into, put a piece of masking tape on the wire and write on it with marker as to what it was connected to, pull the old harness, install the new harness, and then using the old harness as a road map, plug the new wires in.

[73Formula]

mmmm you all got me thinking- the only thing that I have a question about is: I am planning on restoring the AC in the car- it is an original AC car but has been ripped out. Is it possible to install the harness for AC when I dont have it yet? I dont want to have to get two harnesses.
Thanks KC

[Kevin]

I think the AC harness may be separate.

Check here  http://wiringharness.com/ That's who I ordered from. Search their catalog.

[RENOVATIONS]

Yes, you can install the separate mini harness for A/C and simply leave it disconnected and wired out of the way till later

[brian c]

There's a couple different pieces to the AC harness. The good news is this: Neither of them are part of the engine OR forward light harnesses. The AC harness is completely separate so you can buy it at a later date.

I'm making this very easy on you aren't I? 

[73Formula]

Well the good and bad- the harnesses are about 165 each- but they dont have the engine harness for my engine - it takes about 6-8 weeks to make from this company. I may still have ta of florida do it- I was going to have them do some other stuff anyway along those time lines.