Transmission Fluid Temperature Sensor 1
This code indicates an issue with the transmission fluid temperature sensor.
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 sensor measures the temperature of the transmission fluid to help the computer adjust transmission performance.
What the computer is actually seeing
The transmission control module expects to see a voltage signal from the temperature sensor that varies based on the fluid temperature, typically between 0.5V (when cold) to 4.5V (when hot).
What a healthy reading looks like
The sensor should output between 0.5V to 4.5V corresponding to -40°C to 150°C (-40°F to 302°F).
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.
- 1Check the transmission fluid level and condition. Ensure it is clean and at the correct level. Decision Point: If fluid is low or dirty, service accordingly.
- 2Inspect the wiring and connectors of the transmission fluid temperature sensor for damage or corrosion. Decision Point: Repair any damage or corrosion found.
- 3Using a multimeter, test the voltage at the sensor connector with the key on, engine off. Expected voltage should be between 0.5V and 4.5V. Decision Point: If voltage is out of spec, replace the sensor.
- 4If the sensor voltage is normal, check for fault codes related to the transmission control module. If more codes are present, diagnose them accordingly.
Common causes
- Faulty transmission fluid temperature sensor
- Wiring issues or short circuits
- Poor connections at the sensor or module
- Faulty transmission control module
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally safe, but you may experience transmission shifting issues.
Will this code come back after clearing it?
If the underlying problem isn't fixed, yes, the code will likely reappear.
Why does this code sometimes pair with others?
It often pairs with codes related to other sensors or systems that depend on transmission performance.
Working a real vehicle right now?
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