DTC P1638 Chevrolet
Generator F Terminal Circuit Malfunction
Generator F Terminal Circuit Malfunction
Description
No CKP, CMP or Generator codes set, key on and the PCM detected the PWM signal was from 10-40% for over 6 seconds; or with the engine speed under 3000 rpm, the PCM detected the PWM signal was less than 5% for 6 seconds. The PCM uses the generator field du
Cause and Solution
Generator connector is damaged or has high resistanceGenerator field duty cycle signal circuit is open or shortedGenerator is damaged or has failedPCM has failed
Video Guide
Diagnostic Info
- DTC Code: P1638
- Brand: Chevrolet