Transmission Fluid Temperature Sensor 1
Transmission fluid temperature sensor signal is out of range.
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What it means (plain English)
The transmission fluid temperature sensor is reading a temperature outside the normal range, which might indicate overheating or a problem with the sensor itself.
What the computer is actually seeing
The ECM monitors the transmission fluid temperature sensor output voltage, which should typically range between 0.5 to 4.5 volts. A reading below 0.2 volts or above 4.8 volts is considered out of parameters.
What a healthy reading looks like
Expected voltage range is 0.5V to 4.5V based on temperature range of -40°F to 257°F (-40°C to 125°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 wiring and connectors for the transmission fluid temperature sensor. Look for frays, corrosion, or a loose connection. Is the wiring intact? If yes, go to step 2. If no, repair the wiring/connectors and retest.
Common causes
- Faulty transmission fluid temperature sensor
- Bad wiring or connector issues
- Low transmission fluid level
- Overheating transmission due to other faults
Typical repair cost
$$ - $$$
Related codes
Frequently asked questions
Can I drive if this code is active?
Yes, but it's not recommended to drive long distances as it could lead to transmission damage.
Will this code come back after clearing it?
It may return if the underlying issue is not addressed.
Why does this code pair with other codes?
Transmission issues often affect multiple sensors and can reveal a systemic problem.
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