Diagnostic Aids
WARNING: This page is about a different car, the 2013 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.
DTC U0121:00 indicates that the ABS module cannot communicate over the HS-CAN bus. This could be due to a DTC being set in the ABS or a circuit fault in the HS-CAN bus. Do not install a new PSCM as part of the repair for a PSCM DTC U0121:00.