TRSSensor

Transmission Range Sensor (TRS)

Group: Transmission

The TRS reports the position of the automatic transmission shift lever (P, R, N, D and manual ranges). It allows the engine to start only in P or N and turns on the reverse lights.

Contents

What does the TRS sensor do?

It is a multi-position switch attached to the transmission selector shaft. Each position closes a different combination of contacts. The transmission computer uses it to know which gears it may engage, and the starting system uses it to prevent the engine from starting in gear. It is also called the neutral safety switch or multifunction switch.

Where is it located?

On the outside of the automatic transmission, on the shift lever shaft. On some models it sits inside, on the valve body.

Signal type and reference values

  • Multi-contact switch (a code for each position) or a Hall sensor with a digital output.
  • The scan tool shows the position the computer sees: P, R, N, D, 3, 2, 1.

Values are a guide only: always check the manufacturer's data for your vehicle.

Symptoms of a bad TRS sensor

  • The engine does not start in P, or only starts in N.
  • The reverse lights do not come on.
  • The transmission engages the wrong gear or goes into limp mode.
  • The gear indicator on the dashboard does not match the lever.
  • Codes P0705 to P0709.

How to test the TRS sensor step by step

  1. Move the lever through every position and check on the scan tool that the computer sees the same one.
  2. Check the adjustment of the shift cable: a misadjusted cable gives the same symptom.
  3. Measure continuity in each position using the chart in the manual.
  4. Check whether fluid has got into the connector.

Trouble codes related to the TRS sensor

Frequently asked questions about the TRS sensor

Why does the vehicle only start in neutral?
Usually because the range sensor is misadjusted or worn in the P position.
Can the TRS be adjusted?
On many models, yes: you loosen it and rotate it until the N position lines up with a mark or an alignment pin.

Updated September 25, 2026. Values are a guide only: always confirm them in the service manual for your engine.

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