Error code

OBD2 P0904

OBD2P0904
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

Gate Select Position Circuit.

Severity

moderateCan drive, but shifting issues may occur.

Summary

P0904 indicates a malfunction in the transmission gate select position circuit, which is used to monitor gear selection and transmission operation.

Symptoms

  • Erratic shift patterns
  • Harsh or delayed gear engagement
  • Missing gears

Common Causes

  • Misalignment of the GSP sensor after repair work
  • Faulty gate select position (GSP) sensor due to corrosion or damage

Diagnosis

  1. Check the alignment of the GSP sensor using a scan tool
  2. Inspect and repair any damaged wiring or connectors between the ECM/TCM and GSP sensor

Fixes

  • Adjust the misaligned GSP sensor
  • Replace a faulty gate select position (GSP) sensor

FAQ

What should I do if my car is experiencing shifting issues with P0904?

Check the alignment of the GSP sensor and inspect wiring for any damage or corrosion.

Can a faulty gate select position circuit cause other transmission problems?

Yes, it can lead to erratic shift patterns, harsh shifting, or missing gears.

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.