P111A on 2019-2020 Mazda CX-5 (Grand Touring Reserve, Signature) — Engine Coolant Over Temperature Condition - Forced Limited Power
1 vehicles · 1 makes · $2,300-$9,500 repair
Most Reported On
P111A is an OBD-II diagnostic trouble code meaning “Engine Coolant Over Temperature Condition - Forced Limited Power.” Mazda-specific code seen across SkyActiv-G gasoline and SkyActiv-D diesel engines. The PCM watches engine coolant temperature through the ECT sensor and sets this code when coolant temperature exceeds the calibrated over-temperature threshold (Mazda service information cites roughly 122 C / 252 F) for a set period. To protect the engine, the PCM forces a reduced-power mode. The driver typically sees the high coolant temperature warning light plus a noticeable loss of power. This is a protective action, not a nuisance code - the engine is either actually overheating or the PCM believes it is, and continuing to drive risks head gasket or piston damage. Note that Mazda issued service information for 2014-2015 Mazda3 vehicles where this set from a sensor/wiring fault rather than true overheating. This code is most commonly reported on 2019-2020 Mazda CX-5 (Grand Touring Reserve, Signature), with repair costs ranging from $2,300 to $9,500.
Common Causes
Typical Repair Cost
Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
P111A does not use the standard P/B/C/U prefix. It may be a manufacturer-specific code, so verify that a scanner supports your exact year, model and module before buying.
FAQ
What does P111A mean?
P111A stands for "Engine Coolant Over Temperature Condition - Forced Limited Power." Mazda-specific code seen across SkyActiv-G gasoline and SkyActiv-D diesel engines. The PCM watches engine coolant temperature through the ECT sensor and sets this code when coolant temperature exceeds the calibrated over-temperature threshold (Mazda service information cites roughly 122 C / 252 F) for a set period. To protect the engine, the PCM forces a reduced-power mode. The driver typically sees the high coolant temperature warning light plus a noticeable loss of power. This is a protective action, not a nuisance code - the engine is either actually overheating or the PCM believes it is, and continuing to drive risks head gasket or piston damage. Note that Mazda issued service information for 2014-2015 Mazda3 vehicles where this set from a sensor/wiring fault rather than true overheating.
What are the most common causes of P111A?
The most common causes of P111A are: Low coolant level or air trapped in the cooling system after a leak or service, Failed or stuck-closed thermostat, Cooling fan or fan control module not commanding the fan on, Faulty engine coolant temperature sensor or its wiring reporting false high readings, Failing water pump or a restricted/clogged radiator, Head gasket failure pushing combustion gases into the cooling system. The specific cause varies by vehicle.
How much does it cost to fix P111A?
Repair costs for P111A range from $2,300 to $9,500, depending on the vehicle and root cause.
Which vehicles are affected by P111A?
Au7o has documented P111A across 1 vehicle models from 1 manufacturers: Mazda.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.