P0760 is a diagnostic trouble code (DTC) for "Shift Solenoid C Malfunction". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $114.99. Looks like your transmission control module and shift solenoid are acting up. The P0420 is related to the catalytic converter efficiency. 1. level 1. · 1 mo. ago · edited 1 mo. ago. I can't remember exactly what the issue was but my dad's Chrysler had the exact same issue and i think it was a sensor on the transmission.