Temperature Sensor 1 Failure
The engine control unit detected an issue with Temperature Sensor 1.
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 computer isn't getting the right temperature readings from the sensor, which can mess with engine performance and fuel management.
What the computer is actually seeing
The engine control module (ECM) expects to see a voltage from the temperature sensor that varies between 0.5V (cold) and 4.5V (hot).
What a healthy reading looks like
Voltage should be around 2.5V at room temperature (20°C or 68°F). Maximum should be close to 4.5V at operating temperature.
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.
- 1Inspect wiring and connectors for damage or corrosion related to Temperature Sensor 1.
- 2Check the temperature sensor resistance. It should be within manufacturer specs—usually around 2,500 ohms at 25°C.
- 3Test the voltage output of the sensor while the engine is running. It should vary with temperature changes—0.5V to 4.5V during operation. If not, replace the sensor.
- 4If the sensor tests fine, check the ECM input by testing voltage on the signal wire to ensure it's getting the correct readings.
Common causes
- Faulty temperature sensor
- Wiring harness issues (damaged or corroded)
- Bad connector at the sensor or ECM
- ECM software bug
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable, but engine performance may be affected. Fix it soon.
Will this code come back after clearing it?
It may return if the underlying issue isn't resolved.
Why does this code pair with SPN 2983?
SPN 2983 often indicates issues with the same sensor parameters, leading to related faults.
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