Exhaust Temperature Sensor 1
The engine control unit has detected a fault with the 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 exhaust temperature sensor measures how hot the exhaust gases are; if it fails, the engine doesn't know if it's running too hot or too cold, which can affect performance and emissions.
What the computer is actually seeing
The computer sees voltage readings from the exhaust temperature sensor. Normally, you should see a voltage between 0.5 to 2.5 volts under regular operating conditions. If it falls below or above this range, or if it's inconsistent, a fault code is triggered.
What a healthy reading looks like
0.5 to 2.5 volts under normal operation, with a resistance of 1000 ohms at around 25°C (77°F).
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 connector for the exhaust temperature sensor. Look for frays, corrosion, or disconnection. → If damage is found, repair or replace as needed.
- 22. Measure the voltage at the exhaust temperature sensor connector—should be between 0.5 to 2.5 volts while the engine is running. → If outside this range, the sensor may be faulty; go to step 3. → If within range, check further upstream for related issues.
- 33. Disconnect the sensor and test its resistance with a multimeter; it should be around 1000 ohms at 25°C (77°F). → If resistance is out of spec, replace the sensor. → If resistance is good, inspect the engine control unit for faults.
Common causes
- Faulty exhaust temperature sensor
- Wiring damage or corrosion in the sensor circuit
- Connector issues or poor connections
- Exhaust leaks affecting sensor readings
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
It’s moderate severity; the vehicle may run poorly and could affect emissions, but it’s usually drivable.
Will the code come back after resetting?
If the underlying issue hasn’t been fixed, yes, the code will likely return.
Why does this code seem to appear with SPN 6327?
SPN 6327 is the second exhaust temperature sensor; issues often affect multiple sensors in the same system.
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