Yep that is correct! Jeep has a special procedure using the DRBIII scanner that activates the ABS motor. Unfortunately, after market scanners don't have the ability to Address the ABS System in this manner.
I have read that everything from getting air into the ABS to causing internal damage.
Things do get complicated when you start putting computers in cars! So something as simple as bleeding the brakes has become a dealer job or buy your own DRBIII scanner, $$$$.
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