Faulty battery terminals aren’t always easy to spot with a visual inspection. Follow this Real Fix to see how a bad battery terminal causes a P1633 code.
Model
2000 Ford Pickup F350 Super Duty 6.8L
Complaint
The customer states the check engine light is on.
Cause
Connected a scan tool and found code P1633 – KAM Voltage Too Low. Performed a visual inspection of the battery power wiring harness and battery cable terminals and detected no obvious faults. Used a scan tool to observe the Parameter Identification Keep Alive Power (PID_KAPWR). Wiggle tested the battery cables to simulate road shock and found KAPWR varied as the positive battery cable was wiggled at the battery cable terminal. The results of these tests indicated the battery cable terminal was faulty.
Correction
Replaced the battery cable terminal, cleared codes, performed a road test and verified the vehicle operated properly. The check engine light did not illuminate and no fault codes returned.
Courtesy of Mitchell 1 SureTrack Real Fixes.