Transmission Fluid Temperature Sensor A Circuit
The ECM has detected a problem 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 transmission fluid temperature sensor measures how hot the transmission fluid is. If it reports a temperature that’s out of range, it can affect shifting and performance.
What the computer is actually seeing
The ECM expects voltage signals from the sensor that correlate to certain fluid temperature ranges, typically between 100°F (38°C) to 240°F (116°C). If the signal is too high (>4.9V) or too low (<0.5V), it sets this code.
What a healthy reading looks like
Transmission fluid temperature values should typically be between 100°F (38°C) and 240°F (116°C). A good reading should be around 180°F (82°C) when the vehicle is in normal operation conditions.
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 wiring and connector for the transmission fluid temperature sensor. Look for any signs of damage, corrosion, or loose connections. If found, repair or replace as needed. DECISION POINT: Is the wiring and connector good? If no, repair the wiring/connectors and retest. If yes, proceed to step 2.
- 22. Measure the voltage at the sensor while the engine is running. Use a multimeter to check for voltage between 0.5V and 4.9V. DECISION POINT: Is the voltage reading in this range? If no, replace the sensor. If yes, proceed to step 3.
- 33. Check the fluid level and condition in the transmission. Low or contaminated fluid can affect sensor performance. DECISION POINT: Is the fluid level correct and in good condition? If no, fill or change the fluid and retest. If yes, proceed to step 4.
- 44. If all previous tests are normal, consider possible ECM issues. Reprogramming or replacing the ECM may be needed.
Common causes
- Faulty transmission fluid temperature sensor
- Wiring harness issues (fraying, shorting, or open circuits)
- Poor electrical connections
- Fluid contaminants affecting sensor performance
- ECM faults
Typical repair cost
$$
Related codes
Frequently asked questions
Can I drive the vehicle with this code?
It's drivable, but you'll notice shifting issues and it may lead to transmission damage if not addressed.
Will the code come back after clearing it?
If the underlying problem isn't fixed, yes, it will likely come back.
Why does this code sometimes pair with SPN 0717?
SPN 0717 also deals with transmission temperature issues, possibly indicating a failing temperature sensor or wiring issue.
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