Engine Aftertreatment Temperature Sensor 2
This code indicates an issue with the second temperature sensor in the aftertreatment system.
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 fault means the second temperature sensor in the exhaust system is malfunctioning, which could affect emissions control and performance.
What the computer is actually seeing
The ECU expects the second aftertreatment temperature sensor to give a temperature reading between 0 to 500 degrees Celsius while in operation.
What a healthy reading looks like
2nd aftertreatment temp sensor should read between 150-300°C during normal operation, not exceeding sensor limits.
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 connectors of the aftertreatment temperature sensor for damage or corrosion. If found, repair or replace as necessary. Decision: Were any issues found with wiring/connectors? Yes: Fix the issue. No: Proceed to step 2.
- 22. Check the resistance of the aftertreatment temperature sensor using a multimeter. Temperature sensors should show a resistance value consistent with expected temperature. Decision: Is the resistance within specifications? Yes: Proceed to step 3. No: Replace the sensor and retest.
- 33. Start the engine and monitor the second temperature sensor reading with a scan tool or graphing tool. Decision: Is the reading normal while the engine is at operating temperature? Yes: Code may be intermittent or caused by external factors. No: Replace the sensor and retest.
Common causes
- Faulty aftertreatment temperature sensor
- Wiring issues or poor connections to the sensor
- Exhaust system leaks or damage affecting sensor readings
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable, but you should fix it soon to avoid potential emissions issues.
Will this code come back after clearing?
If the root cause isn't fixed, yes, the code is likely to return.
Why does this code pair with other SPN codes?
Many times when one sensor fails, it can affect the operation of other related systems, causing multiple codes.
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