Thread: '00 Grand Prix - ABS/TCS light always on and Speedometer Error while in Neutral

I have a '00 Grand Prix GTP and been having ABS/TCS problems (light always on) for 6 months now. I took it to a local mechanic (not dealership) and told me that it's the ABS CPU unit that's under the hood. I asked if it's a wheel hub/ABS sensor issue (or wiring from/to the ABS CPU), but he said no. How likely is it for the ABS CPU unit to malfunction?

Recently, I've also noticed that when I'm cruising and put my car in neutral, the speedometer and my HUD goes to zero. If I put it back into drive, then the car shows the correct speed.

Now at this point, I'm thinking that it's a wheel/hub/wiring problem rather than an ABS CPU unit problem. What do you guys think? It seems to be a pretty common problem.

BTW, my car doesn't shut off on its own. (http://www.grandprixforums.net/car-r...ies-33478.html)

Thanks in advance

Edit: Engine was scanned and there were 3 codes (but I can't remember the codes, and I can't find the paperwork). =(

those are all signs of a bad hub.

edit: did he scan it?

get a code, i have the same issue, its called the EBTCM, its behind the air box and infront of the master cyclinder. I have the same issue, you have to ckeck the wires and grounds to make sure nothing is wrong there and then its the module more that likely and they can be pricey.

Heres a pic

speedo to 0 in neutral are signs of a bad hub.