P0825: Quest lever switch produces an impossible input pattern

The 2004 Nissan Quest RE5F22A manual labels its lever-switch circuit procedure P0825. The TCM detects an impossible input pattern from the switch built into the selector assembly. The diagnostic question is whether the controller sees a coherent ON/OFF state.

Use the relevant transmission diagnostics

Nissan explicitly classifies this procedure as a non-OBD-II self-diagnostic item and gives the CONSULT-II display name for the gear-lever switch. That distinction matters when a basic emissions-only scanner cannot retrieve the same information. Lack of a result on such a tool does not prove that the selector circuit passed.

The initial check reads the switch's ON/OFF action in transmission data. The documented electrical references distinguish a grounded ON state from the OFF state. A state that fails to change directs attention to the switch, its ground and the path to the TCM.

An impossible pattern is not a worn-gear diagnosis

The possible causes are harness/connector faults and the lever switch. The factory procedure tests continuity and checks for shorts before moving to TCM input/output assessment. It does not diagnose damaged internal gears from this code.

The confirmation routine is performed with ignition on and engine stopped under a specified overdrive-switch condition. Preserve that setup when interpreting a recheck. Record the actual lever state, the reported data state and the circuit inspection outcome; these provide a concrete basis for repair instead of replacing the selector assembly from the code title alone.

Documented application

2004 Nissan Quest factory AT manual, RE5F22A transmission section, January 2005 revision. The source labels P0825 as a non-OBD-II enhanced diagnostic item.

Source

2004 Nissan Quest Factory Service Manual: AT, physical PDF pages 568, 570, 571.