Diagnostic article Generic OBD-II
P0955: Manual-shift switch range and stuck-state faults are different
SAIC P0955 separates an invalid manual-shift signal from a signal stuck in an upshift or downshift state.
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Documented application
SAIC Motor MG4 EV UK Guided Fault Finding DTC Support v1.02; documented P0955 monitor only; per-build equipment applicability not established.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
The SAIC gateway chapter describes the upshift/downshift switch as integrated with the shifter control unit. P0955:1C means its signal is outside the recognized OFF, ON, UP and DOWN states. P0955:96 identifies a signal stuck in UP or DOWN. These are related but different control-input observations.
Valid state versus changing state
For :1C, recovery requires the signal to return to the recognized state range. For :96, the source requires the signal to change. A value that looks valid at one instant therefore does not settle a complaint that the input remains stuck.
The monitor runs with stable, normal battery voltage and an awake controller. The documented response is to disable the switch function, not to declare that transmission gears or clutches have failed.
Keep applicability bounded
This procedure appears in the MG4 UK source compilation, which contains multiple equipment implementations. Its presence is not proof that every MG4 has this manual-shift arrangement. The vehicle's actual shifter system must be established before using the procedure.
The supported cause list includes the shifter control unit and gateway, and the diagnostic sequence considers module information and connection or circuit evidence. It does not authorize replacing the shifter based on the five-character code alone. A technician should preserve the failure type and input behavior, then verify the appropriate range or state-change requirement after a supported repair.
This interpretation is limited to the cited MG4 UK manual revision; it does not establish applicability to every MG4 build or another manufacturer.
Source: SAIC Motor MG4 UK Guided Fault Finding DTC Support v1.02.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
Auto Shift Manual Mode Circuit
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT