Coolant Level Sensor Fault
The coolant level sensor is reporting an incorrect coolant level.
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) checks coolant levels through a sensor. If the sensor gives a reading that doesn't match the actual coolant level — like a reading of 0.5 volts when it should be around 1.5 volts — it throws this code. Basically, the sensor is either faulty or the coolant is low.
What the computer is actually seeing
The ECM sees abnormal voltage from the coolant level sensor, typically below the expected range for a valid coolant level.
What a healthy reading looks like
Normal readings from the coolant level sensor should be between 1.0 to 3.0 volts depending on the coolant level.
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 coolant level in the reservoir; it should be between the 'MIN' and 'MAX' markings.
- 22. Inspect the wiring and connectors to the coolant level sensor for damage or corrosion.
- 33. Use a multimeter to test the coolant level sensor output. Check for expected voltage between 1.0 to 3.0 volts based on coolant level.
- 44. If the sensor voltage is within range, consider replacing the coolant level sensor. If the voltage is out of range, repair the wiring or connectors as needed.
Common causes
- Faulty coolant level sensor
- Wiring issues between the sensor and ECM
- Low coolant level in the reservoir
- Connector corrosion or damage
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally safe to drive unless the coolant level is actually low. Check fluid levels immediately.
Will the code come back after clearing?
If the underlying issue isn't fixed, yes, it will likely return.
Why does this code sometimes pair with SPN 1213?
SPN 1213 indicates a related issue with the engine temperature sensor, which can affect coolant readings.
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