Exhaust Gas Temperature Sensor 1 - Circuit High
The exhaust gas temperature sensor is reporting a high voltage condition.
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What it means (plain English)
The exhaust gas temperature sensor measures the temperature of the gases coming out of the engine. If it's showing too much voltage (like over 5 volts), the engine control unit thinks there's a problem with how hot those gases are, which can lead to engine performance issues.
What the computer is actually seeing
The engine control module (ECM) detects that the voltage from the exhaust gas temperature sensor is higher than expected, indicating a potential sensor fault or wiring issue. The typical voltage range is 0.5V to 4.5V, and anything above that indicates a fault.
What a healthy reading looks like
0.5V to 4.5V under normal operating 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.
- 11. Check the exhaust gas temperature sensor wiring for any visible damage or shorts. Measure the voltage at the connector with the engine running; it should be between 0.5V and 4.5V. Does the voltage exceed 4.5V?
- 22. If voltage is high, disconnect the sensor and check again. If the voltage drops back to normal range, replace the sensor. If voltage remains high, check the wiring from the sensor to the ECM for shorts to power.
- 33. Inspect and clean the connector pins for corrosion or poor contact. Reconnect and retest the sensor voltage. Is it back to normal?
- 44. If issues persist, check for fault codes related to the ECM itself; consider reprogramming or replacing if necessary.
Common causes
- Faulty exhaust gas temperature sensor
- Wiring issues (shorts or opens)
- Poor connector contact or corrosion
- Faulty ECM (rare)
Typical repair cost
$$ - $$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's safer to fix soon; while it may still run, high exhaust gas temperatures can lead to serious engine damage.
Will this code come back after clearing it?
If the underlying issue isn't resolved, the code will likely come back after clearing.
What happens if I ignore this issue?
Ignoring high exhaust gas temperatures can lead to overheating components, reduced fuel efficiency, and potential engine failure.
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