P0801Reverse Inhibit Control Circuit/Open
- Generic OBD-II code · Powertrain
- How the car detects it
- On GM manual gearboxes (Tremec T56/TR6060 in Corvette, Camaro, CTS-V and ATS-V) the engine module drives a solenoid that blocks reverse while the car moves forward. P0801 means its control circuit is open. GM's tables describe the check: the low-side driver's internal diagnosis flags an open line with at least 9 V and the engine above 250 rpm, 20 failures in 25 samples of 250 ms – about 6 s; in 2006 a 5 s comparison of commanded and actual driver state. GM rates it type C, emissions-neutral and without MIL, from 2019 with a 'service vehicle soon' note. Depending on how it fails, reverse cannot be engaged or is no longer blocked. The title was updated to the current J2012 wording with '/Open'.
- What you may notice
- Reverse hard or impossible to engage
- Reverse no longer blocked
- Service note in the driver display, usually no MIL
- Likely causes
- LikelyConnector at the reverse inhibit solenoid loose or corroded
- PossibleSolenoid coil open
- PossibleHarness between engine module and gearbox damaged
- RareEngine module driver faulty
- Repair
- Medium · Often possible to do yourself.Typical cost: €30 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.