The engine control module (ECM/PCM) has detected an internal fault: control module programming error. This is a serious internal computer issue that may require PCM replacement or reprogramming.
Find certified mechanics near you who can diagnose and repair P0602.
For informational purposes only. Diagnostic trouble codes are starting points for diagnosis, not definitive answers. Always consult a certified mechanic for proper diagnosis and repair. Estimated costs vary by vehicle, location, and shop rates.