Exhaust Gas Temperature Sensor 1 Circuit Low
There's a problem with the temperature reading from the exhaust gas 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 exhaust gas temperature sensor is showing a low reading, which means it might be wiring or the sensor itself that’s faulty. It should normally show higher temperatures when the engine is running.
What the computer is actually seeing
The engine control module (ECM) detects that the output from the exhaust gas temperature sensor 1 is below expected levels, typically under 0.5 volts, indicating a circuit issue or a faulty sensor.
What a healthy reading looks like
The exhaust gas temperature should be around 300-600°C (572-1112°F) when the engine is at operating temperature; the sensor voltage should be between 0.5V and 4.5V under normal 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.
- 1Check the exhaust gas temperature sensor connector for corrosion or damage; repair as necessary.
- 2Measure the voltage at the exhaust gas temperature sensor while the engine is running; it should be between 0.5V and 4.5V.
- 3If the voltage is low, inspect the wiring between the sensor and ECM for shorts or breaks; repair any found issues.
- 4If wiring checks out, replace the exhaust gas temperature sensor and retest.
- 5If the new sensor still shows low values, consider an ECM fault.
Common causes
- Faulty exhaust gas temperature sensor
- Damaged wiring or connectors
- Faulty ECM
- Short or open circuit
- Corrosion at the sensor connector
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but you should address it soon to prevent potential exhaust or emission system damage.
Will this code come back after I fix it?
If the underlying issue is resolved, it shouldn't come back.
Why does this code pair with SPN 2774 or SPN 2780?
These codes relate to similar sensor functions, so issues affecting one can likely affect others.
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