This morning when we started our 1999 Chevrolet Venture van our anti-lock brake light came on. We drove it to where we were going and parked it for about an hour, when we cranked it up again the anti-lock brake light turned itself off after the self check as it has always done before. Problem solved, right? Wrong, later in the day my wife had to take the van out once again and she noticed that the turn signals on the instrument panel were lighting up every time she depressed the brake. One other sort of odd thing also was occuring with the brakes and the turn signal, it will signal quickly when you depress the brakes (if you have the turn signal engaged – like when you need to signal to make a turn), when you release the brake the signal goes back to its normal flash timing. Also my wife experienced the ABS light turned back on in mid trip. One other bit, sometimes my AC fan don’t want to start when you turn it on but eventually starts to blow.
I have seen a connection between ABS light and battery light.Get a complete electrical system check-out (battery and cables,parasitic draw,charging system output)is this the original battery? Delco batteries of that year have a problem with acid leakage at the postive terminal.have it checked.Hope you dont need a alternator I have done one on your model and its not fun.When people describe such odd symptons my experience tells me to start at the battery,maybe others go about it different.Then you get the one in one thousand rodent damaged car and it didnt matter where you started.