My car a 1.5 with 3.0 just started to show a BSM: Isolation Warning (#19) and then later we saw a BSM: Isolation Fault 283. I checked the WiKi and could not find any details. Occasionally when very wet and humid I would get the BSM: Isolation fault with the contactors closed (#286) and a short drive always cleared the error and allowed me to charge. But this was different as the warning showed up after driving a while and while warm (88F) and humid (about 80%) it was not wet or raining. When the warning hit we still had full power and was able to drive but it alerted us about 4 times on the drive, which is of concern. The alerts hit after driving about 30 miles. Just 3 days earlier I took a 400 mile drive in it with no issues.
It is the 400V Eberspacher controller. A friend took it out and lay it in the sun or on the heating to get the damp out. Since then no issues anymore. I had the same last year in July when it was extreme hot (40 degrees Celsius). There seem to be alternatives to purchase from GS Technology in Switzerland.
I don't think they work on the old 1.5 units. Can you post a picture of your 400v controller to see if it's possible?
Thought so too, but apparently in extreme heat in the sun outside temperature high and high humidity it fails as well.
An isolation fault is when a high voltage circuit has some resistance to ground, so it could be any high voltage circuit getting wet. The 1.5 controllers were a lot better than the later models, so my guess is that something else got damp.
Sorry for reviving an old thread. My 1.5 just started producing error 19s (isolation warning). This happened after I had my roadster parked outside for several weeks (I know .... :-( ) any suggestions where I start Troubleshooting? Is it safe to take the car for a drive in hopes of drying out the moisture?