91 Passat Charging problems????

[deltalock]

I am at my wits end with my 91 passat 2.0 liter, 16v. The battery always dies. I had the alternator tested off of the car, it's ok. The battery is ok. the wiring seems to be ok. and the load relay clicks fine when I turn the ignition key to the on position. When you measure the voltage from the alternator, it goes from 12 volts up to 14 volts as the car warms up???? I put in a new brush/ regulator assembly into the alternator, no luck. When I put a test light on the smaller wire coming off of the alternator, with the engine running, the light comes on dim and the charge light on the dash board comes on. I believe that this is normal but note that the charge light is not on at any other time. The main wire coming off of the alternator lights the test light bright at the alternator, at the starter, and at the battery. The ground wires have been removed, cleaned and placed back on the car. Please help me!!!
Troy.

[boschmann]

Are you saying the battery light in the dash doesn't come on with the key on & engine off? Do you have the alternator with the white plastic plug in connector (3 wires)?

[deltalock]

Thank you for responding boschman, the alternator is the type with 2 connections, one wire is the heavy gauge that goes to the starter, the other is a smaller ( regular gauge ) which goes to the harness. The charge light comes on when you turn the key to the on position to indicate that it is working, however, when you turn the engine over and it is running, the charge light does not come on. The charge light comes on when you hook up a test light to the smaller wire coming out of the alternator and again the test light is dimmer on that wire than it would be on any other live wire. I've had two mechanics, not very vw. experienced ones, look over the problem and they are baffled. I was advised by them to look for a bad circuit, I found one - interior lights, removed the fuse, no luck with correcting the problem.
I did notice that one time when she wouldn't start, I jump started her and all of a sudden the dash lights got brighter, I drove her to work , turned the engine off and then I turned her over with no problem. It seems like the shock or nudge from the jump start had something to do with the temporary correction of the problem???? I have never experienced the like of this ever!! Any ideas? Troy.

[deltalock]

Boschman, the charge light does not come on when the key is turned to the on position with the engine off. The charge light only comes on when you put a test light on the little blue wire coming off of the alternator. Thankyou Troy.

[boschmann]

If the light doesn't come on in the dash then the alternator will not charge. You need to follow the little blue wire back to the dash light & look for a broken spot. If none are found try replacing the LED light bulb in the cluster.

[deltalock]

Thank you Boschman, I'm going to get it into my inlaw's garage tommorow and I'll let you know what I find.

[deltalock]

Boschman, gotta give you credit, I resoldered the led charge light in the cluster as I could hit the dash by hand and make it come on with the key in the on position. PROBLEM SOLVED, YOU ROCK!!!!! Thank you Boschman, you know more than the mechanics that were unable to determine the cause of the charging problems. Thanks again, Troy.

[kkkmc]

Boschman, I have also a VW passat '91.the same charging problem. A mechanic change my alternator last April/04. but lately my battery keep dying on me. I replace d battery but after couple of week wont start again .so , I took it to another mechanic and told me alternator is not charging. so I went back to the first mechanic and change it again. after changing the alternator still the same no charge. now he told me to take it to another mechanic. he don't know now. do you think the problem is the same like deltalock? pls. help me.Thank's

[deltalock]

Originally Posted by kkkmc

Boschman, I have also a VW passat '91.the same charging problem. A mechanic change my alternator last April/04. but lately my battery keep dying on me. I replace d battery but after couple of week wont start again .so , I took it to another mechanic and told me alternator is not charging. so I went back to the first mechanic and change it again. after changing the alternator still the same no charge. now he told me to take it to another mechanic. he don't know now. do you think the problem is the same like deltalock? pls. help me.Thank's

Hello there, please make sure that your charge light comes on when the key is turned to the on position w/o the engine running. Check the cable that goes from the negative battery post to ground on the starter. I have learned that the long bolt on the starter that the neg. cable is connected to comes loose commonly. I had a mechanic tell me that I needed a new alternator, however, a bad ground in the dash cluster making the charge light stay off was the problem with my Passat. There is also a relay switch above the fuse panel that affects the charging of the battery, check it. Use the following url to locate the relay switch in the fuse panel. http://volkswagen.msk.ru/electro/b3/...fuse_90-91.pdf
You will need a pdf reader like Acrobat which is free to download, good luck., Troy.