Might be that one or more of the ABS sensors are bad. When I first got my Trep one of the sensors were bad so that every so often when I would brake the ABS would activate for no reason. I believe the ABS light would come on some times too.
I'm not sure if there is an engine light code for this but you can try using the engine code retrieval procedure listed in the 1'st gen How-To section of this site.
You'll need a scanner to determine the code...mine has been coming and going as long as i've owned it, i know mines either a dirty sensor or a loose connection, but it hasnt bothered me enough to fix it. might try to clean all the sensors and plugs with some eyther...worked for me in the past
mostly im just trying to see if it's going to cause me any problems, if it's just the sensor then it shouldnt be too much of a problem, i tried the code retrieval already and it just did 55 which was the end so it apparently had no problems, at least none that can be retieved that way
you have no code because you scan the PCM but with a scan tool you can scan the abs module and have a code. Many time is the sensor. I found a good trick to check the sensor witout a scan tool. I jack the car, unplug abs sensor, took a multimeter and check for ac volts coming from the sensor. The sensor should make ac volt when you turn the wheel.
Might sound funny but pull out your instrument cluster and clean the contacts. I pulled mine to replace a bulb and then it started the same thing with all my lights. I cleaned the contacts and it hasn't done it since. Was just dirt on the connetion in the dash.