Transmission Fluid Temperature Sensor 1 - Sensor Range/Performance Problem
This code indicates a problem with the transmission fluid temperature sensor's performance or range.
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 fluid temperature sensor is telling the computer that the fluid temperature is outside what it's meant to be; this could happen if there's a fault in the sensor or the wiring going to it.
What the computer is actually seeing
The ECM expects the transmission fluid temperature between 150°F and 220°F (65°C to 104°C) during normal operation. If the temperature reading is significantly lower than 20°F (-7°C) or higher than 300°F (150°C), this code will trigger.
What a healthy reading looks like
Transmission fluid temperature should normally be between 150°F and 220°F (65°C to 104°C).
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. Inspect the transmission fluid level; it should be within the manufacturer's specified range.
- 22. Check the wiring and connectors to the transmission fluid temperature sensor for any signs of damage, corrosion, or loose fits.
- 33. Use a multimeter to test the resistance of the transmission fluid temperature sensor; it should fall within the expected range at operating temperature. Use the sensor specification to confirm.
- 44. If the sensor readings are out of range (indicating a fault), replace the sensor. If the wiring is damaged, repair it and retest.
- 55. Clear the fault code and monitor for reoccurrence. If the code comes back, further diagnose the ECM's response or check for other related faults.
Common causes
- Faulty transmission fluid temperature sensor
- Wiring issues to the sensor
- Corroded connectors or loose connections
- Low transmission fluid level
- Faulty ECM (rare)
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's usually safe to drive but fix it soon to avoid transmission issues.
Will this code come back after clearing it?
If the underlying issue isn't resolved, yes, the code will likely return.
Why does this code sometimes appear with SPN 5476?
SPN 5476 relates to the same sensor; they can be triggered by similar faults.
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