what could cause the abs light to stay on e36?
It could be any number of things - from something as simple as a fuse to the ABS module or sensor itself. If you live in a cold climate where they use road salt, it is usually a sensor as they just corrode over time. You're asking a very specific question without giving any specifics, however. Have you done any brake work lately? Have you modified the brake system in any way? Has the vehicle been in a front end collision? What environment do you live in? These are all things that have to be taken into consideration.....
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