Engine Exhaust Gas Temperature Sensor 1 Circuit
Indicates a problem with the engine's exhaust gas temperature sensor 1 circuit.
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)
This code means that the computer detected an issue with the temperature sensor measuring the exhaust gases, which should usually show a voltage signal corresponding to the temperature of the exhaust gas.
What the computer is actually seeing
The engine control module (ECM) looks for a voltage signal from the exhaust gas temperature (EGT) sensor 1, which should typically range from 0.5 to 4.5 volts. If it's outside this range or not responding, this code is triggered.
What a healthy reading looks like
Voltage from sensor should be between 0.5V (cold) and 4.5V (hot, around 900°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. Inspect the EGT sensor 1 connector and wiring for damage or corrosion. Repair or replace as necessary. Decision: If fixed, clear code and test drive. If not, proceed to step 2.
- 22. Measure the voltage at the EGT sensor 1 connector with the key on and engine off. Confirm voltage between 0.5V and 4.5V. Decision: If voltage is out of range, replace the EGT sensor 1. If within range, proceed to step 3.
- 33. Check for continuity in the wiring from the sensor to the ECM. Look for shorts or opens. Decision: If wiring is okay, replace the ECM. If wiring is faulty, repair as needed.
Common causes
- Faulty exhaust gas temperature sensor 1
- Wiring issue or corrosion in the sensor connector
- Short circuit or open in the sensor circuit
- ECM software glitch
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive my vehicle with this code?
It's generally safe to drive, but it's imperative to fix this soon as it can affect engine performance and emissions.
Will this code come back after I clear it?
If the underlying issue isn't resolved, yes, the code will likely return.
Why does this code pair with SPN 2602?
Both codes relate to exhaust gas temperature sensors, indicating potential issues in the EGT monitoring system.
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