Gear Shift Indicator Signal
Indicates an issue with the gear shift indicator signal from the transmission.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The transmission is sending the wrong signal about what gear it is in, which can cause shifting issues or erratic behavior.
What the computer is actually seeing
The engine control module (ECM) expects a voltage signal from the transmission, typically around 0.5 to 4.5 volts, reflecting the current gear position.
What a healthy reading looks like
0.5V to 4.5V according to gear position (1st gear = ~0.5V, 2nd gear = ~1.0V, etc. up to 4th/5th gear = ~4.5V).
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the transmission fluid level and condition. Ensure the fluid is clean and at the proper level. Decision: If low, top off or change fluid; recheck code.
- 22. Inspect wiring and connectors for damage, corrosion, or loose connections between the transmission and ECM. Decision: Repair any issues found; recheck code.
- 33. Use a scan tool to check the voltage signal from the gear position sensor at the transmission. Decision: If outside 0.5V to 4.5V range, replace the sensor.
- 44. If no wiring or sensor issues, check for ECM/TCM software updates. Decision: Update software if available, then recheck the code.
Common causes
- Faulty position sensor on transmission
- Wiring issues or bad connectors
- Software glitches in the transmission control module (TCM)
- Transmission fluid low or old.
Typical repair cost
$$-$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable but may experience shifting problems; fix soon.
Will this code come back after clearing?
If the underlying issue isn't fixed, yes, it will likely return.
Why does this pair with other SPNs?
Codes represent linked issues; they often appear together due to common faults in the transmission system.
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