I got a solid CEL yesterday. 2003 OBS, 175k kms.
At first, I tightened the gas cap. I know my timing belt is due, so I was wondering if the CEL would come on around this many kms just to force me to go in and get the timing belt done. But after today's drive, I think it's the ABS.
I just replaced the drums, rotors, pads & shoes about a month ago. The car seems to be working great, including braking. However, I had to brake hard a couple of times today (almost missed a turn-off, then wasn't paying attention coming up to a red light - I was actually thinking about my brakes!) and although the braking power was good, the ABS didn't kick in quite in the same way I'm used to. I heard squeeling tires both times, and the brake pedal - although I think something was happening - wasn't normal for an ABS event.
Any suggestions on how to troubleshoot or what to look for? All I had time to do so far is check the fluid level.