Pcm Code E068, Cruise Control Command Problem: Description
WARNING: This page is about a different car, the 1992 Cadillac Seville and 1992 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
PCM continuously compares cruise control servo position sensor to throttle position. This diagnostic test monitors for a throttle position greater than 20 degrees and servo position greater than commanded by PCM for 2 seconds.