Exhaust Gas Temperature (EGT) Sensor 1 Circuit Low
EGT Sensor 1 is reporting a low signal voltage.
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 measures how hot the exhaust gases are. If the sensor sends a low voltage, it means it's possibly faulty or not detecting the temperature properly—usually below 0.1 volts when it should be higher during normal operation.
What the computer is actually seeing
The engine control unit is receiving a steady voltage drop indicating a low temperature reading, typically less than 0.4 volts when the exhaust should be showing at least 350°F (about 177°C) during normal operation.
What a healthy reading looks like
0.5 to 5.0 volts under normal exhaust conditions, correlating to exhaust temperatures from around 200°F (93°C) to 1,500°F (815°C).
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 condition of the wiring and connectors at the EGT sensor. Look for corrosion, breaks, or shorts. Decision point: Are the wires and connectors in good shape?
- 22. Measure the voltage at the EGT sensor connector while the engine is running. Expect between 0.5 and 5.0 volts. Decision point: Is the voltage within this range?
- 33. If voltage is low (<0.5 volts), check the sensor itself using a multimeter. If the sensor's resistance is outside the expected range (typically 5-15 ohms), replace the sensor. Decision point: Is the sensor faulty?
- 44. If the sensor and wiring are fine, check for exhaust leaks near the sensor. Decision point: Are there any exhaust leaks?
- 55. If all checks are clear, consider considering the ECM; it may require reprogramming or replacement.
Common causes
- Faulty EGT sensor
- Wiring issue (frayed or shorted wires)
- Poor connector contact
- Exhaust leaks near sensor
- Faulty ECM (Engine Control Module)
Typical repair cost
$$ - $$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It’s not ideal, as it can affect engine performance and emissions. Fix it soon.
Will this code come back after clearing it?
If the underlying issue isn't resolved, the code will likely return.
Why is this paired with other codes?
Multiple codes can indicate a broader issue in the exhaust system, so look for common faults.
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