Contour Enthusiasts Group Archives Forums General Troubleshooting Alternator Woes (a bit long)

Here's the problem...

My friends mother has a 96 GL 4cyc. The recent problem has been that it will not charge. The key to knowing when it happens is the charge dummy light does not come on when you start the car.

Troubleshooting:
2 new alternators
2 1" grounding straps incase there's a bad ground somewhere.
10 busted nuckles

We have found that if you remove the green wire from the alternator, ground it (which turns on the light on the dash) and replace the green wire, it will charge fine for X number of days. I am speculating that it may be corrosion on one of the pins in one of the connectors between the interior of the car and the engine compartment. (this is speculation because we have not checked this out yet)

The odd part is the grounding of the green... Is this some sort of remote turn-on for the regulator like a remote turn-on on a stereo amp? Is there something else I should look at? Any help would be greatly appreciated.

Thanks in advance.

Jim

Are there megafuses on 1995's? I'm not sure, but other's have had the same problem on later model V6's and the cause was a blown 60A megafuse, located under the upper manifold. I know that doesn't help you with a 4cyl Zetec, but perhaps someone else knows?

-Lance

Hummm, there are megafuses on this, I thought all of them were in the underhood fuse panel. They are all good, but I will look to see if there are others.

Thank you Lance

Hello, everyone! I am the registered owner of the contour in question here. I just pulled the 175A Megafuse and tested it. Turned out OK. I am really puzzled by the way the car is responding. It will charge fine for hours or days, and then suddenly will stop charging. As you all have read above, theis is the second alternator in the car, so that eliminates the possiblity of that being the culprit. Battery is new, as well.

The only sign that the alternator has stopped charging is the absence of the idiot light at startup. If I remove the plug from behind the alternator and ground the green wire to the negative battery post while the ignition is on, the light will illuminate (as per the test outlined in the factory service manual). I then reinstall the plug in the alternator and then it charges fine for an undetermined amount of time before the problem repeats itself.

I obviously don't trust the car to travel more than 2 or 3 miles from home and am running out of possible solutions. I already sanded clean all electrical connections that I can find. It is not an issue as faar as grounding of the alternator itself, as I have taken care of that with 2 braided ground straps, just to be safe.

Can anyone offer any more advice on how to take care of this problem? It makes replacing the A/C compressor seem easy (just did that one, too!)

Thanks, all!

John

Alt needs 12 volts from battery via fuse 4, obtained via red wire next to green wire at alt connector, in order to have output. Sounds like the connector is causing intermittent problems with both circuits although I'm not sure you could exclude faulty internal connections at alt terminals.

p.s.

Originally posted by FeiroGT:

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The only sign that the alternator has stopped charging is the absence of the idiot light at startup.

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Notwithstanding this statement I presume you are measuring volts at battery or seeing lights dim to indicate alt not charging.

You are correct. I have confirmed that the alt is no longer charging by testing for voltage with a meter.

Does anyone know the routing of the green wire...more specifically, what connectors it goes through and their locations?

Thanks!

John

Both circuits mentioned in my prior post go thru' the 42 pin connector at driver's strut tower, then diverge to their respective destinations. IMO since you have proved the green wire circuit ok by grounding, no need to follow it back to dash.

Edit: Phrase in italics added.

OK, I just checked out the 42 pin connector. Thing, is, that the car is not acting up right now so I'll have to drive it for a bit until it acts up again.

If I understand you correctly, the green/black wire goes from the alternator to the 42 pin connector and then where? My assumption is that it goes thru the dash light bulb and then to switched power from the ignition. Am I correct?

Thanks!

John P.

Your assumption correct.

Don't discount internal alternator fault, perhaps intermittent, in your diagnostic thinking.