VW T4 Forum - VW T5 Forum banner

1 - 1 of 1 Posts

7 Posts
Discussion Starter #1
Hi All,
I have a relatively new to me 1997 2.4d T4, the electrical system and battery have been going strong until recently (excluding an issue with glow-plug relay).

Recently I had some welding done to deal with some rust on the floor pan and the van drove and started grand the next two days after that. The following day I stripped out some of the dash trim - diff lock, glove box and fuse box housing in order to touch them up. The evening following this I turned the key and found no power to the instrument cluster at all. Further inspection has revealed that the battery had drained to ~2v. This was Tuesday after last being driven on Sunday. This battery will not fully charge with my home charger.

I stuck another good enough battery in and the engine fires up fine except I have noticed some white / grey smoke coming from the area around the alternator and it seemed hot. Inspection of wiring showed no melted insulation or terminals.

I removed the alternator and it does appear very dirty (courtesy of some debris and an oil leak). Whilst it was out I used an multi-meter to carry out a parasitic draw test. The only circuit drawing any amps is feeding interior lights and ODO etc. This is showing a draw of 2.6 on the 20mA resolution. When I remove this fuse the draw returns to zero and the ODO turns off. Is this draw expected on this circuit? I assume this would be for the ODO to stay on. :*

Next, I disconnected the multi-meter and reconnected the alternator. When I connected the multi meter again on the 20mA scale it immediately blew the fuse in the meter. I can however get a reading on the 10A scale - I think it settled down to 0.01 after the same time it would take for the previous test (without alternator) to settle down to 2.6.

The only other troubleshooting I have tried is a diode test between the alternator casing and the large terminal post. With the meter positive on the terminal I see a reading of ~500 and with the meter negative on the terminal I see a reading of 1.500. As this is over 1 on the dial I am not sure how to interpret this result. My meter manual says a reading of 1 for a good diode.

Would anyone have any suggestions towards next troubleshooting steps or what could be the issue? I am considering getting the alternator checked and potentially re-furbed if possible as the bushes are also very worn.

Thanks for any input,

1 - 1 of 1 Posts