Coolant Flow Rate Check Fault
Engine control module detected an inconsistent coolant flow rate.
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's computer is checking the coolant flow and finding something's off, which can lead to overheating.
What the computer is actually seeing
The engine control module (ECM) monitors signals from the coolant flow sensor and other temperature sensors to ensure proper coolant circulation inside the engine.
What a healthy reading looks like
Coolant flow rate should be within 5-15 liters per minute at operating temperature. Sensor signals should typically be 0.5-4.5 volts while running, depending on the specific engine design.
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: Ensure it is at the proper level and look for any leaks. If low, top off and recheck for code after 10-15 minutes of driving.
- 22. Inspect wiring and connectors: Look for damaged wires or corroded connectors at the coolant flow sensor. Repair any issues found. Recheck for code.
- 33. Test the coolant flow sensor: Use a multimeter to check the voltage output while the engine is running (should be 0.5-4.5 volts). If outside this range, replace the sensor and clear the code.
- 44. Check for coolant flow: If the sensor checks out but the code returns, verify that coolant is flowing properly using a flow meter to confirm it reaches expected rates (5-15 L/min). If not, investigate for blockages.
- 55. Clear the code and drive the vehicle: After replacing any faulty parts, clear the code and monitor the vehicle for reoccurrence.
Common causes
- Faulty coolant flow sensor
- Coolant level low or air in the system
- Cooling system blockage or restriction
- Wiring issues or connector problems
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to fix it soon; driving can lead to overheating and engine damage.
Will the code come back after repairs?
If all issues are resolved and parts replaced, the code should not reappear.
Why does this code appear with other codes?
Interconnected issues in the cooling system often trigger multiple codes related to temperature or flow.
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