Alternator Failure After Engine Wash A3 ALH?

Hello!
I've been having the following problem since yesterday:
After the engine cleaning, the charging indicator light remains on, and the alternator is not charging the battery.
Did the washing process damage the voltage regulator? All the cable connections to the alternator are dry and in good condition. Even warming up the alternator to dry it out and blow away any moisture didn't help.
How should I proceed (troubleshooting, removing the alternator cover, replacing the voltage regulator, costs)?

Best regards & thank you,
Waldi.

Vehicle: A3 TDI, Engine Code: ALH, Year: 1998.

Waldi wrote:

How should I proceed from here (troubleshooting, removing the cover of the alternator, replacing the voltage regulator, costs)?

Hi,

I don't know how to disassemble your bra.

But you can check the regulator yourself (with some hardware) as follows:
Attach a test lamp to the carbon brushes.
Apply a variable DC voltage between the terminals of the excitation diodes and ground.
The test lamp should light up at a voltage of approximately 14 to 14.5 volts, and it should turn off at a higher voltage, with the cutoff threshold being a few millivolts higher than the turn-on threshold.

If the regulator is doing that, it's most likely okay, and the problem lies elsewhere.

Does voltage reach the terminal for the charging indicator light on the port side when the engine is not running?

I used to have that too...

After a night of drying, everything was back to normal.

m;

Hello!
I've already replaced the voltage regulator, and everything is working again. It wasn't a pleasant experience to get to, but it helped.
'First, my dealer told me that the regulator wasn't sold separately, but only as a complete alternator replacement, for something like 300 euros plus tax. That's shocking! But another Audi dealer actually had the regulator in stock. It cost 52 euros.'

Regards,
Waldi.

if it's a Bosch-Lima, even a visit to the Klingons might help .

A quick look at the catalog 'Parts for Starters and Generators' can be helpful...

CU Gremlin.

Hm, so, the ALH Golf 4 always has the option of regulator replacement for the 120-type wipers from Valeo and Bosch.

Hmm, so the ALH Golf 4 always has the option of changing the regulator when using 120-type wipers from Valeo and Bosch.


The regulator can actually be replaced in almost any alternator.
(I haven't seen a single one in 12 years where that wasn't the case).
Of course, it requires more effort for some people (removing the engine, disassembling it) than for others.

Hmm, yes, but I heard that VW used a similar Lima manufacturer in the Golf 4, where it supposedly shouldn't work. However, I don't know the manufacturer's name or whether that information is correct.

I have a 120A Hitachi alternator in my G4 ALH. According to the dealer, it is definitely not possible to replace the regulator (which is unfortunately defective in mine).

I'd be happy to be proven wrong, as it would save me a lot of money!

I have a 120A Hitachi alternator in my G4 ALH. According to the dealer, it is definitely not possible to replace the regulator (which is unfortunately defective in mine).



Can you give me the Hitachi number for the Lima?

@ MartinR

The label on the battery shows the following information: Hitachi 120A, 14V.

VW Part No.: 028903029G

LR 1120-701

I'm not sure if the second one is a Hitachi model.

Thank you, Thomas.

I'll try to find out something about that number if I have the chance.