Engine Exhaust Temperature Sensor 1
This code indicates a fault with the engine exhaust 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 engine has a sensor that measures the temperature of the exhaust gases. If the sensor fails, it can send a wrong temperature reading to the engine computer, affecting how the engine runs.
What the computer is actually seeing
The engine control module (ECM) expects to see temperature readings from the exhaust temperature sensor in a specific range (usually around 800-900°F during operation). If readings are below 100°F or exceed expected maximums, it triggers a fault code.
What a healthy reading looks like
The exhaust temperature should range between 800°F and 900°F during normal operation. Sensor readings under 100°F or above 1000°F are telling the ECM there’s a problem.
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 exhaust temperature sensor connector for corrosion and tightness. Decision: If damaged, repair or replace the connector. If okay, move to step 2.
- 2Measure the voltage at the exhaust temperature sensor connector with the engine running. You should see voltage between 0.5V and 4.5V depending on temperature. Decision: If voltage is out of range, replace the sensor. If within range, proceed to step 3.
- 3Check the wiring between the sensor and the ECM for continuity. Look for shorts or breaks. Decision: Repair any broken connections. If wiring is good, consider replacing the ECM.
Common causes
- Failed exhaust temperature sensor
- Wiring issues (shorts or opens)
- Faulty ECM
- Corrosion or contamination at connector
- Exhaust leaks affecting sensor location
Typical repair cost
$$$
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Frequently asked questions
Is it safe to drive with this code?
It's best to avoid extended driving, as it can affect engine performance and emissions.
Will this issue come back after clearing the code?
If the underlying problem isn't fixed, the code is likely to return.
Why do I see this code with other sensor codes?
Related codes often indicate issues with the exhaust system components that are interconnected.
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