P1285 1997 FORD F150 Possible Causes
- Engine overheating
- Low engine coolant level
- Faulty Cylinder Head Temperature (CHT) sensor
- Cylinder Head Temperature sensor harness is open or shorted
- Poor electrical connection in the Cylinder Head Temperature sensor circuit
How is the P1285 1997 FORD F150 code repaired?
Start by checking the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Check Engine Light On (or Service Engine Soon warning light)
P1285 1997 FORD F150 Meaning
The Cylinder Head Temperature (CHT) sensor is a thermistor device where resistance changes with temperature. The electrical resistance of a thermistor decreases as temperature increases and resistance increases as temperature decreases. The variable resistance affects the voltage drop across the sensor terminals and provides electrical signals to the Powertrain Control Module (PCM) corresponding to temperature.
The CHT sensor is installed in the aluminum cylinder head and measures metal temperature. The CHT sensor can provide comprehensive engine temperature information and can be used to infer coolant temperature. If the CHT sensor transmits an overheating condition to the PCM, the PCM initiates a fail-safe cooling strategy based on CHT sensor information. A cooling system issue such as low coolant level or coolant loss can cause overheating. This could damage major engine components. Using both the CHT sensor and the fail-safe cooling strategy, the PCM prevents damage by enabling engine air cooling and backup capability.
The Diagnostic Trouble Code (DTC) indicates detected cylinder head overheating, meaning an engine overheating condition has been detected by the cylinder head temperature sensor.