Exhaust Gas Temperature Sensor 1 Low
This code indicates that the exhaust gas temperature sensor is reading lower than normal.
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)
Your vehicle's computer expects a certain temperature reading from the exhaust gas temperature sensor, which helps monitor the engine and emissions systems. If the sensor reads too low, under 100°C (212°F), it throws this code because it thinks the sensor is malfunctioning or there's a problem with the system.
What the computer is actually seeing
The PCM sees a signal from the exhaust gas temperature sensor that is below its expected range, often near or at 0 volts when it should be at least 0.5-2.5 volts indicating an operational temperature.
What a healthy reading looks like
Normal operating range for the exhaust gas should be between 200°C to 700°C (392°F to 1292°F) during operation, depending on load and RPM.
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 wiring and connectors leading to the exhaust gas temperature sensor for damage or corrosion: if any issues, repair or replace as needed.
- 22. Measure the voltage at the exhaust gas temperature sensor harness, expecting it to be between 0.5 to 2.5 volts at idle. If not in range, proceed to step 3; if in range, consider sensor replacement.
- 33. Inspect the exhaust system for leaks in proximity to the sensor; repair any found.
- 44. Replace the exhaust gas temperature sensor if wiring is good and no leak is found; clear the code and test drive the vehicle.
Common causes
- Faulty exhaust gas temperature sensor
- Open or short in the wiring or connectors
- Exhaust leaks near the sensor
- Poor ground connections or power issues
- PCM software issues
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally safe but you should fix it soon to avoid potential issues with emissions and further exhaust system damage.
Will this code come back after I clear it?
If the underlying issue isn't resolved, yes, the code will likely return.
Can this code be related to other issues?
Yes, low exhaust gas temperature readings can affect engine performance and fuel efficiency.
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