Engine Exhaust Temperature Sensor Circuit Low
The engine exhaust temperature sensor is reporting a low voltage condition.
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 is. If it's below what it should be, it may indicate a wiring issue or a failed sensor.
What the computer is actually seeing
The engine control module (ECM) looks for a voltage from the exhaust temperature sensor between 0.5V to 4.5V. If it gets below 0.5V consistently, it triggers this code.
What a healthy reading looks like
0.5V to 4.5V DC signal from the sensor during operation.
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.
- 1Check the exhaust temperature sensor connector for corrosion or damage.
- 2Inspect the wiring for any visible signs of wear, fraying, or disconnections.
- 3Using a multimeter, measure the voltage at the exhaust temperature sensor connector. It should be between 0.5V and 4.5V.
- 4If the voltage is out of range, check for continuity in the wiring back to the ECM. Repair any broken wires found.
- 5If the wiring checks good and the voltage is low, replace the exhaust temperature sensor.
Common causes
- Faulty exhaust temperature sensor
- Damaged wiring or connectors
- Open circuit in the sensor's harness
- Ground issue with the sensor
- Incorrect exhaust system modifications
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
Yes, but the vehicle may not perform optimally and fuel efficiency could be affected.
Will this code go away on its own?
Not likely. It will remain until the problem is repaired.
Why do I also see codes for SPN 813 or SPN 815?
These codes relate to other sensors in the exhaust temperature system and often appear if there is a shared issue.
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