1 Fast Car

OK, have read a lot of posts so I've gotten far enough I need to know what fork in the road I should take.

I have a 1990 944 S2 Cabrio. When starting it up the seat belt light comes one and airbag light. Then airbag clicks off for 1 second then back on (seat belt light stays on). The ABS light does not come on at this point. Then when I start moving the car within about 15ft and less than 10MPH the ABS light comes on before I touch the brake.

I have checked the wheel sensor resistances at the ABS control brain box in the passenger side (under glove box) and they are all close to 1K (996 - 1018 ohm).

I've had a 928 S4 and that had an ABS light at start up and was a simple $100 relay but in this case the car has to be in motion.

I also read that the Bosch control box is slightly different for 928 and 944 cars as the # pulses from the toothed thing on the wheel hubs are not the same. My control brain has on it 928.618.119.05 and I think Bosch # 0265103035 085. I was thinking that was my problem (maybe earlier owner changed it out as ABS light has been on since I bought the car) but on eBay I see the same # box listed as taken from an 89 S2 so unless someone looks in their car with working ABS that does not seem to be it.

So before I start digging deeper what are the next things that should be checked? Do I go right for using a wire brush and air to clean off the sensor tips and the ring that makes it pulse or do I need to dig for relays on the ABS unit under the right front wheel.

I'm in the concord NH area in case anyone has a spanner / hammer or something that can just be plugged in to tell me the fault.

Thanks for any help you can give in advance!

Brad