Originally Posted by niero
I'll ask my mechanic to check those. You wouldn't happen to have any other ideas on what could turn the ABS light on?
There are numerous problems that could turn the light on, from a slightly misadjusted wheel sensor to complete failure of the ABS computer. There's little point in just guessing, if you can't see an obvious potential cause like a broken wheel sensor wire, you have to pull the trouble codes, which requires a professional-level scanner (the cheap ones aimed at DIY mechanics can't pull codes from the ABS, and there's no equivalent of the key dance trick for ABS codes).
I've just received the 1993 ZJ ABS diagnostic manual in the mail - $10 from eBay. It's got full diagnostic/repair flowcharts for every possible ABS malfunction, and there are a lot of tests that you need to do to isolate certain issues.