Engine Exhaust Temperature Sensor 1
The exhaust temperature sensor 1 is reading outside the normal range.
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What it means (plain English)
The exhaust temperature sensor measures how hot the exhaust gases are. If it's too cold (below 300°F or 150°C) or too hot (over 1500°F or 815°C), the computer thinks there’s a problem.
What the computer is actually seeing
The ECM monitors the voltage signal from the exhaust temperature sensor, expecting a range between 0.5V (cold) and 2.5V (hot). Anything outside this signal range triggers a code.
What a healthy reading looks like
Normal operation should see values from the exhaust temp sensor around 800°F (425°C) to 1200°F (650°C) during normal driving.
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 exhaust temperature sensor. Look for damage, corrosion, or loose connections before testing anything else.
- 22. Measure the signal voltage with a multimeter while the engine is running. You should see a signal voltage between 0.5V and 2.5V under normal conditions.
- 33. If the sensor is reading below 0.5V or above 2.5V, replace the exhaust temperature sensor and retest.
- 44. If the sensor is within range but the code persists, check for exhaust leaks or insulation damage. Fix as necessary and retest.
Common causes
- Faulty exhaust temperature sensor
- Wiring issues or short to ground
- Connector corrosion or damage
- Exhaust leak affecting temperature readings
Typical repair cost
$$$
Related codes
Frequently asked questions
Can I still drive my truck with this code?
Yes, but you should fix it soon, as it can affect engine performance and emissions.
Will this code come back if I clear it?
It might come back if the underlying issue isn't resolved.
Why is this code paired with other codes?
Multiple codes can indicate a complex issue, such as a faulty sensor affecting different parameters related to exhaust temperature.
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