p1638

[gmc6]

Ok i am having issues with the charge indicator light it stays on all the time.Code is p1638 for F-termnial circuit. The alternator has been replaced resently due to this issue but it is still there.System is charging at 13.2v koer.Checked all pwr cables to batt and to alternator and they are within spec.Hooked up my scanner to check the duty cycle of the f terminal and koer it stays at 0% no matter the rpms. Any body had any issues like this i really would aperciate the help. And also i just replaced the cluster thinking it was bad but it still has the same issue.

[GasGuzzler]

Remind me tomorrow. Sounds familiar.