Engine Exhaust Temperature Sensor 1
This code indicates a problem with the Engine Exhaust Temperature (EET) sensor 1 signal.
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 Engine Control Module (ECM) is getting readings from the exhaust temperature sensor that are outside the expected range, which can affect performance and emissions.
What the computer is actually seeing
The ECM expects a voltage signal from the EET sensor typically between 0.5V to 4.5V, corresponding to temperatures from about 200°F to 2000°F. If the signal falls outside of this range, it triggers the code.
What a healthy reading looks like
0.5V to 4.5V for temperatures approximately 200°F to 2000°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. Inspect the wiring and connector for the EET sensor for damage or corrosion. Repair as necessary. Decision: If wiring is damaged, repair and retest; if OK, proceed to step 2.
- 22. Measure the voltage at the EET sensor connector with the key on and engine off. Expected voltage should be between 0.5V and 4.5V. Decision: If voltage is within range, replace the EET sensor; if voltage is out of range, proceed to step 3.
- 33. Check the sensor ground and supply voltage. Ensure proper voltages are present (usually around 5V supply and a good ground). Decision: If ground or supply is faulty, repair it; if good, replace the EET sensor.
Common causes
- Wiring issues or shorts in the EET sensor circuit
- Faulty Engine Exhaust Temperature Sensor 1
- Corrosion or poor connection at the sensor or ECM
- Exhaust leaks affecting temperature readings
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's advisable not to drive extensively until repaired, as it can impact emissions and performance.
Will this code come back after a repair?
If the underlying issue is fixed, the code should not return.
Why does it pair with code SPN 4531 or SPN 4532?
These codes may indicate related sensor faults or other problems in the exhaust temperature measurement system.
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