U0121 on the 2007 Chevrolet Corvette
The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.
Nobody has written a description of this code yet.
| 08-07-30-021H | 2017-08-15. Service bulletin. This technical bulletin provides repair information to correct customer concerns of loss of high speed GMLAN communications, intermittent no crank, IP gauge fluctuation, intermittent door lock cycling /chime operation, various IP warning lamps illuminated, transmission may not shift, communication DTCs U0073, U0100, U0101, U0102, U0109, U0121 or U0140 set. |
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| 08-07-30-021G | 2012-04-28. Service bulletin. GM: LOSS OF HIGH SPEED GMLAN COMMUNICATIONS, INTERMITTENT NO CRANK, IP GAGE FLUCTUATION, INTERMITTENT DOOR LOOK CYCLING, INTERMITTENT CHIME OPERATION, VARIOUS IP WARNING LAMPS ILLUMINATED, TRANSMISSION MAY NOT SHIFT, COMMUNICATION DTCS U0073, U0100, U0101, U0102 U0121 OR U0140 SET (REPAIR TERMINALS IN TRANSMISSION HARNESS CONNECTOR, REPAIR OPEN OR SHORTED GM HIGH SPEED LAN CIRCUITS, OPEN OR SHORTED DATA LINK RESISTOR, CORROSION OR POOR CONNECTIONS IN VARIOUS CONTROL MODULE CONNECTORS). *JS |
| SB-08-07-30-021 | 2008-08-28. Service bulletin. LOSS OF HIGH SPEED GMLAN COMMUNICATIONS, INTERMITTENT NO CRANK, IPC GAUGE FLUCTUATION, INTERMITTENT DOOR LOCK CYCLING, TRANSMISSION MAY NOT SHIFT, DTCS U0073, U0100, U0101, U0102, U0121, U0140 SET (REPAIR BACKED OUT TERMINAL IN TRANSMISSION HARNESS CONNECTOR). VEHICLES WITH 6 SPEED 6L80 (RPO MYC), 6L90 (RPO MYD) OR HYBRID TWO MODE 2M70 AUTOMATIC. INCLUDING 2008 TAHOE AND YUKON HYBRID MODELS. *PE UPDATED 3/28/11. INCLUDING SIERRA, SILVERADO AND ESCALADE HYBRIDS. *PE |
3 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.