Alternator problem...???

[storagedaddie]

Great site...

Problem started yesterday. AC quit blowing cold, both fans were running as they should. Next trip out, about 20 minutes into it, the ABS, the triangle with circle, the airbag, then brake light warning lights came on. Followed by the low coolant "red" warning light. Pulled over checked fluids, all was fine. Noticed all dash lights, head lights, etc, started to dim. Dash lights got so dim they almost went out. After sitting for several minutes restarted car, no warning lights on. About 10 minutes later the process started again.

Let the car sit overnight, and went for test drive. All dash lights etc, were bright, seemed normal, no trouble starting. 20 minutes into trip, the same process started again. After a couple of test runs the battery was finally dead.

My gut was telling me it was the alternator, due to dimming of lights while driving, and battery finally going dead. Read several forums, and all was pointing to the alternator.

I removed the alternator and went into a auto parts store for check. It tested good...! Battery had to be charged for a bit, but it tested good too!

My inclination is still alternator.

Is it possible that it quits working properly once it gets hot? So while cool, for the first few minutes it works fine, once it heats up it quits charging? Or does an alternator go completely out once bad?

I think I read a thread here that the poster only lost charging when the alternator started squealing.

Any suggestions appreciated...

[storagedaddie]

OK... One more option. How about the fuse box on top of the battery?

The spot where the black wire connects is burnt to a crisp. Pretty close to touching the wire next to it. The black wire appears to be the wire going to the alternator.

Thoughts?

[johnmichael]

same thing happened to me multiple times. i ended up cutting that fat black wire further up and attacthing it to the positive terminal, with no fuse at all. it's been 6 months and no problems, the wire never even gets warm.

[Too Cold NB1.8T]

Don't do it, all it would take is a random voltage/current spike and things could get ugly.

Find the culprit that is causing this problem and repair it correctly, just a suggestion.

[pfeifervw]

This is a common problem from what I've heard...the solution is usually something along the lines of replacing the wire to the alternator, replacing that fuse, and the entire battery cover/fusebox.

Good luck,
Matt

[vw87tech]

might need to replace the alternator harness and fuse box over the battery.good luck

[leemoss84]

Originally Posted by storagedaddie

Great site...

Problem started yesterday. AC quit blowing cold, both fans were running as they should. Next trip out, about 20 minutes into it, the ABS, the triangle with circle, the airbag, then brake light warning lights came on. Followed by the low coolant "red" warning light. Pulled over checked fluids, all was fine. Noticed all dash lights, head lights, etc, started to dim. Dash lights got so dim they almost went out. After sitting for several minutes restarted car, no warning lights on. About 10 minutes later the process started again.

Let the car sit overnight, and went for test drive. All dash lights etc, were bright, seemed normal, no trouble starting. 20 minutes into trip, the same process started again. After a couple of test runs the battery was finally dead.

My gut was telling me it was the alternator, due to dimming of lights while driving, and battery finally going dead. Read several forums, and all was pointing to the alternator.

I removed the alternator and went into a auto parts store for check. It tested good...! Battery had to be charged for a bit, but it tested good too!

My inclination is still alternator.

Is it possible that it quits working properly once it gets hot? So while cool, for the first few minutes it works fine, once it heats up it quits charging? Or does an alternator go completely out once bad?

I think I read a thread here that the poster only lost charging when the alternator started squealing.

Any suggestions appreciated...

so, did you ever get this problem sorted out? im having the same problem with my girlfriends car and b4 i put a new alternator on it i was wondering if the wire problem is what was wrong with it.

[Turbomania]

Our alternators have built in regulators that can go bad separately. If the regulator is bad and no fuse is in line, it can allow more than standard voltage to be transfered down the hot wire and into the top of battery fuse and circuit box and can fry this and many other electrical components. It takes much longer than 5 minutes to properly check out an alternator along with the battery. Make sure this main wire is properly sized and is well connected to the high amperage fuse which protects everything. I think it is a 150 AMP fusible link type fuse available at any auto parts store. From what you have said here in your thread, it sounds like it very well could be your alternator/battery connection that is at fault. If the battery turns out to be bad too, replace it with the battery spec'd for the Diesel engine model. It's larger with more cold cranking amps and will fit into the original battery box. Don't allow the battery blanket to be discarded, re-install it for good over all hot and cold weather performance! JK

[slvrbtlboi]

was wondering if this ever got resolved for you, I'm having a similar problem with the fuse box on the battery burning up and was wondering what you did to fix yours?

[kkendric]

Check your voltage at the battery at idle, should be about 14.4 volts. I just had my battery boil off all liquid, my alternator was at 16.9 volys at idle. My new alternator should arrive tomorrow, just installed the new battery. Will let you know if this fixes the problem, it should

[fohveh]

Simply put... ITS THE ALTERNATOR HARNESS WIRE. Overtime it corrodes at the fuseblock end and creates greater and greater resistance over time until the box itself melts. Goodluck with the fuseable link failing, it never works and the box melts and loses contact with the alternator lead. Once the lead is replaced and the fuseblock, if burnt or melted around the alternator contact point you will not have any further issues. By the way check the second red wire as well at the fuseblock that powers all your elays under the dash it usually the next to melt and fail.

[fohveh]

should read "relays" not "elays" sorry about the typo.