2020 - 2021 Corvette: Service Bulletin: #PIP5797: M1L Internal Transmission Faults Related To Components Not Serviceable At The Dealer Level - (Mar 30, 2021)

#PIP5797: M1L Internal Transmission Faults Related To Components Not Serviceable At The Dealer Level - (Mar 30, 2021)

Some customers may comment on a service transmission message or a service engine soon message accompanied by any of the following DTCs:

P2838, P2839 or P283A.

If any combination of two or more DTCs P2838, P2839 or P283A have set current or history, then check circuit integrity on circuit 7812 between the TCM and transmission.  Check terminal tension and for a possible short to ground. If any issues are noted repair as needed and verify vehicle is repaired. If no issues are noted then transmission would need replacement as anything related to the odd shaft module (OSM) is not serviced. 

P1955 and P0867

Any instance where the vehicle has a current or history P1955 and P0867 stored. The Fluid level should be checked and clean procedures outlined in TSB 21-NA-033 should be performed, if DTCs P1955 and P0867 return it is related to a loss of system pressure being investigated by engineering.  The transmission would also require replacement. Note: P1955 usually will not set as the only code so if it is among the codes stored it is likely the cause of the other DTCs.

For either of the above scenarios are present please see latest version of PIP5709.