P0801: manual-transmission reverse-inhibit driver disagrees with feedback

P0801 in the cited 2010 GM table concerns the reverse-inhibit solenoid control circuit on a manual-transmission application. The ECM detects that the driver's commanded state and the actual control-circuit state do not match.

This is not an internal reverse-gear diagnosis

The monitored relationship is electrical. The table does not measure gear engagement or establish damaged internal reverse components. A complaint about selecting reverse should be documented separately from the control-circuit evidence.

It is equally important to preserve the manual-transmission scope. The same summary page contains automatic-transmission request information, but those neighboring rows do not change the P0801 application's stated transmission type.

A valid check requires the running conditions

The row specifies run/crank voltage within its allowed band and engine speed above 600 rpm. It uses twenty failed samples out of twenty-five, sampled every quarter-second. An engine-off continuity inspection can be part of a repair procedure, but it does not itself reproduce this operating monitor.

A useful scan record aligns the reverse-inhibit command with any available circuit feedback and the supply condition. This is an inference from how the monitor compares states, not a substitute for the wiring test in the vehicle service manual.

The code does not identify whether the solenoid, connection or controller driver caused the mismatch. Do not defeat reverse inhibition as a diagnostic shortcut. Locate the actual circuit fault and verify operation through the applicable procedure.

Application limits

Document-level 2010 GM diagnostic table; per-code vehicle/engine/calibration applicability not established.

Source

10OBDG12 Engine Diagnostics, physical PDF pages 97.