Red Light on Dash on, Need Help!

[nick325i]

Well, finally got my alternator on Friday afternoon and it doesn't fit. The studs aren't long enough to go through the fan housing and it didn't come with a nut for the shaft......so I'm making some phone calls tomorrow.....

[James Brown]

me think you got the wrong Alt! probley has the internal regulator,you don't get a nut for the shaft, it goes in the fan and the outer pulley half is the nut.

[Laneco]

Definately have the wrong year alternator. Something here that should be clarified... If you removed the alternator and took it to a shop and it tested fine, how do you know the voltage regulator (external on your car) is OK? After all, that was still on the car when the alternator was at the shop.

Voltage regulators can be "flaky" when they fail. When the regulator on my 81 failed (mine is internal, doesn't matter, does the same thing), my alternator decided it would be really super cool to throw out 19 plus volts. Blew the bulbs on my headlamps which is what got me looking for a problem to begin with. I must say though that the power windows went up and down REAL well - LOL! Red light stays off on an over-charge...

My husband's 85 (another internal) has been acting up. He drove down the an electric shop and had the car tested at the shop. Diagnosed as not-charging (11.5 or so volts), red light on. He brought the car home. It sat a week or so and he fired it up to turn it around so the rear was in the shade instead of the sun and planned to remove the alternator. Guess what? No red light! Threw a voltage meter on it and it was charging at 16.8 to 17 volts... Not good, pulled it and will take it down to the electric shop for a regulator replacement and rebuild as the bearing feels a bit gravely.

Also, let me share a tip a Pelican dude gave me. Find a ground and a hot inside of your car and put your voltage meter to it. Drive like that if you continue to have a problem to diagnose under/overcharge. I popped the clock out and used the hot/ground from the clock for this purpose. Looks goofy, works well.

angela

[bdisco]

[Bulb on the fuel guage is flashing]
Kowalski: Skipper, look.
Skipper: Analysis
Kowalski: It looks like a small incandescent bulb, designed to indicate something out of the ordinary, like a malfunction.
Skipper: I find it pretty and somewhat hypnotic.
Kowalski: That too sir.
Skipper: Right. Rico, Maunal!
[Catches the manual and smashes the bulb with it]
Skipper: Problemo solved.

[Rob G]

Wait for it, Wait for it, NOW.

Originally Posted by bdisco

[Bulb on the fuel guage is flashing]
Kowalski: Skipper, look.
Skipper: Analysis
Kowalski: It looks like a small incandescent bulb, designed to indicate something out of the ordinary, like a malfunction.
Skipper: I find it pretty and somewhat hypnotic.
Kowalski: That too sir.
Skipper: Right. Rico, Maunal!
[Catches the manual and smashes the bulb with it]
Skipper: Problemo solved.

[Gunter]

Originally Posted by nick325i

Thanks for all the help guys. I really appreciate it.

I had the alternator tested at the local auto parts store and they said it is charging. The battery tested bad, but I have since tried a few different batteries that I know are good and it still has the light on.

I've also checked all my wires and cleaned all my grounds. They appear to be good.

Could the voltage regulator be the problem? I have a little experience and usually a bad one causes over-charging, not under-charging, but that is not on a Porsche so I don't know.

The shop that tested the Alternator could have told you if it has an internal or external regulator.
Why not ask them??????????before odering a new alternator????

An external regulator would be located on the left side inner fender of the engine compartment.
Take a picture of the area where the filter is and we'll tell you if you have it.

Why not have your alternator rebuild to have an internal regulator?

It's a lot cheaper than a new one.

[nick325i]

I know for sure it has an external regulator. My local parts store is suppose to have one here for me tomorrow morning. If that doesn't do it then I'm taking the alternator to get rebuilt.

[jagular911]

Having exactly the same problem-not trying to hijack your thread, but ask a simple question.

Does anyone know how to test the regulator?

[Gunter]

Alterator and internal regulator are tested together on the bench.

If you have an external regulator, it's easy for a shop to test it in situ.
They'll put some leads on and tell you if the alternator is charging and if the regulator works.

[nick325i]

Ok, so I replaced the external regulator. Need a little wiring clarification.

New Regulator has: teal, dark brown (maybe black) and red wires

Car has: blue, brown and black wires

I think I know how it goes, but it doesn't seem to be working. Do any of y'all know how the wires match up?

[nick325i]

OK. Finally got the alternator rebuilt.

So now I have a rebuilt alternator (which I assume works) and a new voltage regulator.

Light is still on. Still reading approx. the same voltage at the battery.

Anyone have any other ideas?

And, does anyone know anything about the regulator wiring question above? I want to make sure I am doing it right.

[nick325i]

Ok, another interesting development. When I first start my car. The fuel gauge reads half a tank and if i honk the horn it drops to almost empty.

Does anyone know what that means?

[Gunter]

How do you know that the new regulator matches your alternator?
Take the new regulator and the rebuild alternator to the shop that rebuild it and ask them how the wires go.

Better yet, charge your battery fully, then make an appointment, drive there and let them install and test in situ. Takes no time at all and elimminates any guessing.

[Tarek307]

Another dead end thread where some ****dhhaffhda asks for advice and help then never updates when he finds the solution... sooooo many thread here like this!!

[timmy2]

Well, the OP sold his car in 2010. Maybe he gave up and sold it!

[Tarek307]

Originally Posted by timmy2

Well, the OP sold his car in 2010. Maybe he gave up and sold it!

there are so many issues you go through threads and the OP just doesn't give a crap to update, it drives me crazy, ultimate show of selfishness lol ask for advice then disappear

[Starless]

Originally Posted by Tarek307

there are so many issues you go through threads and the OP just doesn't give a crap to update, it drives me crazy, ultimate show of selfishness lol ask for advice then disappear

I agree, many times you spend hours doing a search for a problem, reading the posts, and at then end, nothing. I will admit that this forum is nowhere near
as bad at this than most others.