Engine Coolant Temperature Sensor 2
This code indicates a problem with the secondary coolant temperature sensor.
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)
There are two sensors monitoring engine coolant temperature; this code means the second one is giving strange readings, which could cause overheating or poor performance.
What the computer is actually seeing
The engine control module (ECM) sees an abnormal signal from the secondary coolant temperature sensor, often below 40°F (4°C) or above 240°F (115°C), which is out of range during normal operation.
What a healthy reading looks like
Normal coolant temperature readings are generally between 180°F (82°C) and 220°F (104°C) for proper engine 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.
- 11. Check the engine coolant level. Ensure it is within the acceptable range. Move to step 2 if okay. If low, top it off, and recheck for the code after some operation.
- 22. Inspect the wiring and connectors at the coolant temperature sensor 2. Look for any corrosion, loose connections, or damaged wires. If okay, go to step 3.
- 33. Test the resistance of the coolant temperature sensor 2. It should typically read around 2.5k ohms at 70°F (21°C). If readings are outside of 1.5k-5k ohms, replace the sensor and retest.
- 44. If the sensor is confirmed functional, check for error signals from the ECM or verify with a scan tool if the error is recurring.
Common causes
- Faulty coolant temperature sensor 2
- Wiring issues or damaged connectors to the sensor
- Coolant leaks causing low coolant levels affecting sensor input
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It depends on symptoms; if the engine overheats or performs poorly, don't drive it until fixed.
Will this code come back after clearing?
If the underlying issue isn't resolved, it will usually return.
Why does this code appear with other coolant codes?
Related issues with coolant sensors can trigger multiple codes if there is a common fault in the system.
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