It sounds to me as if your charging system isn't working properly after the bath. I would assume that this is the case or you lost the poly-belt. In which case you would know. The other remote possibilty is that you had a voltage surge that popped the overvoltage fuse. It is located behind the plastic panel behind the battery. It is in the top of a relay with a clear plastic lid on it. If the fuse is OK, get it towed so you don't loose voltage and break down.
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