Gearbox malfunction message in cluster. DTCs P17D800, P179D00, P174000, P174C, P174B, P174F, P179C, P174A, and/or P174E are stored in the transmission control module. Fault codes and symptom codes must match exactly or this TSB should not be followed. Poor internal contact area on circuit board will lead to faults. Oil additives can cause the plastic circuit plates to delaminate, causing contact loss.