This Preliminary Information communication provides information to the technician about vehicles that may have a repeat service 4 wheel drive message. Technician may find Diagnostic Trouble Codes C0398, C038D or C0397. Technician will need to reprogram the Transfer case control module with latest software available through tis2web. If the vehicle has Regular Production Option Code (NQH) and has a Diagnostic Trouble Code C0398 setting after being Dinghy towed please see the latest version of PIP5217. If the vehicle has a Diagnostic Trouble Code C0398, inspect circuits 7477, 7478, 7479 for any terminal or connection issues between the B2227 Gear Position Sensor and the Transfer Case Control Module and repair as needed.