If your vehicle is equipped with an Autostick transmission/Tiptronic transmission (there are also many other brand-specific names), you can manually control the shift points using a special gate on the gear lever or paddles/buttons on the steering wheel. If there is an intermittent electrical issue in the circuit that includes a transmission shift switch, a mode actuator, and a bundle of wires and connectors, a DTC P0954 will be recorded by the ECU.
How severe is the code?
Having a diagnostic code P0954 is not very serious. It simply means you won’t be able to use the manual shift function.
Symptoms
Symptoms of a P0954 include:
The manual shift function is disabled
Causes
Damaged connectors or wiring
Shift switch failure
How to diagnose the code?
To determine what is causing the OBDII fault code P0954, your mechanic should start by checking the shift mechanism for signs of water damage from spills. The shift switch needs to be tested, and the wiring/connectors should be inspected for signs of damage and corrosion.