DTC U1255: Class 2 Initialization Error: Testing

Clear DTCs and cycle ignition. Check for DTCs. If DTC U1255 exists, use scan tool to establish communication with each module on class 2 data bus. If all modules are communicating properly, go to next step. If any module is not communicating properly, repair or replace as necessary.
Check for intermittent open in Purple wire between individual control modules. See WIRING DIAGRAMS . If circuit is okay, replace PZM. See REMOVAL & INSTALLATION.