What it means
The control module monitors the speed of cooling fan 3 and sets this code when the reported speed exceeds its calibrated limit.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Cooling fan 3 is one of the vehicle’s radiator or cooling-system fans, and its speed signal lets the control module check how fast it is turning. P2CBC sets when the reported speed of fan 3 exceeds the limit calibrated for its operation.
Common causes
Most likely first.
- Fan speed sensor or tachometer signal fault
- Fan control module fault
- Fan motor fault
Symptoms
- Check-engine light
- Cooling fan unusually loud or running faster than expected
How to diagnose it
- Record the freeze-frame data and check live fan-speed data to confirm the fault occurred while fan 3 was commanded to run.
- With the engine off and cool, inspect fan 3 for damage, obstruction, or anything that could affect its rotation.
- Inspect fan 3’s speed-sensor wiring and connectors for looseness, corrosion, or damaged insulation.
- Compare fan 3’s reported speed with its actual operation while the scan tool commands the fan, following the vehicle’s safe test procedure.
- Test the fan 3 speed signal and control module inputs against the manufacturer’s specification before replacing parts.
- If the signal and wiring check out, test the fan control module and fan motor for a fault that could cause excessive speed.
Common fixes
- Remove debris or other obstruction affecting fan 3.
- Repair damaged wiring or clean and secure fan 3’s sensor connectors.
- Replace a faulty fan 3 speed sensor or tachometer, if separately serviceable.
- Replace the fan control module if testing identifies it as faulty.
- Replace the fan 3 motor if it causes the overspeed condition.
Can I keep driving?
Avoid unnecessary driving if fan 3 is audibly running too fast or the vehicle enters reduced-power mode; monitor the temperature gauge and stop safely if the engine overheats. Continued operation can worsen a fan or control-system fault and may compromise cooling.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.