Action Taken When the DTC Sets
WARNING: This page is about a different car, the 2017 GMC Yukon XL, 2017 GMC Yukon, 2017 Chevrolet Tahoe, 2017 Chevrolet Suburban 3500 HD, and 2017 Chevrolet Suburban. However, it is still accessible from the selected car via links, so may be relevant.
P0776
- DTC P0776 is a Type A DTC.
- The TCM commands maximum line pressure.
- The TCM inhibits Tow/Haul mode.
- The TCM freezes transmission adaptive functions.
- The TCM inhibits TAP Up/Down function.
- The TCM inhibits Manual Up/Down Shift with the shift selector.
- The TCM inhibits auto grade braking.
- The TCM limits the transmission to 2nd gear if the output speed sensor signal is less than 1, 400 RPM. No upshift will occur.
- The TCM limits the transmission to 4th gear if the output speed sensor signal is 1, 400 RPM or greater.
P0777
- DTC P0777 is a Type A DTC.
- The TCM commands maximum line pressure.
- The TCM inhibits Tow/Haul mode.
- The TCM freezes transmission adaptive functions.
- The TCM inhibits TAP Up/Down function.
- The TCM inhibits Manual Up/Down Shift with the shift selector.
- The TCM limits the transmission to Reverse gear and 3rd gear operation.
- The TCM inhibits auto grade braking.