This Preliminary Information communication provides information to the technician the steps to diagnose and repair vehicle with a Service Charging System message or Service Engine Soon Malfunction Indicator Lamp and the Engine Control Module may have set a P0621 and/or P0622. These concerns could be caused by the generator wiring harness rubbing on the Air Conditioning compressor line and shorting the circuits. Technician will inspect the generator wiring harness for chaffing and repair as necessary. Install additional conduit to protect the wiring harness from future issues.