This code indicates the Powertrain Control Module (PCM) has received an invalid or implausible signal from the transmission range sensor, also known as the neutral safety switch. The sensor informs the computer which gear selector position is currently engaged, such as Park, Reverse, Neutral, or Drive. When the signal voltage or combination does not match expected parameters, the code is set.
Internal contacts within the sensor wear out or corrode, sending incorrect voltage signals to the PCM.
The sensor is physically installed out of alignment with the manual valve lever, causing a signal mismatch.
Corrosion, fraying, or broken wires in the circuit between the sensor and the PCM disrupt communication.
Leaking fluid into the sensor connector can cause short circuits or signal interference within the harness.
A worn or stretched cable prevents the selector lever and transmission valve from matching positions.
Internal processing failure is rare and should only be considered after all external circuits and components are verified.
The definition is universal; the diagnostics are engine-specific. Open your vehicle for the codes documented for it:
It is not recommended, as the vehicle may start in gear or shift unexpectedly, creating a safety hazard.
No, this code is rarely caused by the computer itself; replacing the PCM without diagnosing the sensor and wiring is usually unnecessary and costly.
The PCM prevents cranking if it cannot verify the transmission is in Park or Neutral to avoid accidental vehicle movement.
Yes, the PCM uses this data to determine shift points and line pressure, so errors can cause harsh or delayed shifts.