What Does P063F Mean?
The PCM/ECM has detected that the engine coolant temperature (ECT) input signal is not present during the auto-configuration process. During power-up initialization, the PCM checks for all required sensor inputs, and the ECT signal was missing. Without coolant temperature data, the PCM cannot properly manage cold start enrichment, cooling fan operation, or emissions control. The driver may notice hard starting, poor cold idle, or inoperative cooling fans.
Common Causes
35%
Disconnected or damaged ECT sensor connector
25%
Open circuit in the ECT sensor signal wiring
20%
Faulty ECT sensor (open circuit internally)
12%
PCM not providing ground or reference to the ECT sensor circuit
8%
PCM internal fault in auto-configuration sensing
Diagnostic Steps
1
Locate the ECT sensor (typically near the thermostat housing) and check the connector for proper seating, corrosion, or damage. Disconnect, clean, and firmly reconnect.
2
With the ignition on, measure the voltage at the ECT sensor connector between the signal wire and ground. On a cold engine, you should see approximately 3–4V; on a warm engine, approximately 0.5–1.5V. If no voltage is present, check the reference/ground circuit.
3
Measure the ECT sensor resistance with the connector unplugged. At room temperature (68°F/20°C), a typical NTC sensor reads approximately 2,000–3,000 ohms. An open reading (OL) indicates a failed sensor.
4
Check continuity of the ECT signal wire from the sensor connector to the PCM connector. Also verify the sensor ground wire has continuity to the PCM ground pin.
5
Clear the code and cycle the ignition to trigger auto-configuration. If the code returns immediately, the PCM is not seeing the signal. If all wiring and the sensor are good, the PCM may need replacement.
Estimated Repair Cost
$25 - $300
Parts + labor, varies by vehicle and location
The PCM/ECM has detected that the engine coolant temperature (ECT) input signal is not present during the auto-configuration process. During power-up initialization, the PCM checks for all required sensor inputs, and the ECT signal was missing. Without coolant temperature data, the PCM cannot proper...
The most common cause of P063F (Auto Configuration Engine Coolant Temperature Input Not Present) is: Disconnected or damaged ECT sensor connector
Typical repair costs for P063F range from $25 to $300, depending on the vehicle, location, and whether you do it yourself or go to a shop.
The vehicle may run but with degraded performance, especially during cold starts. The cooling fans may not operate properly, which could lead to engine overheating. Monitor the temperature gauge carefully. If the engine begins to overheat, stop driving immediately. Otherwise, the vehicle is safe for short trips to a repair facility.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P063F to identify the root cause.
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Quick Info
Category
Powertrain
System
Engine Control System
Difficulty
Type
Generic (SAE)
Recommended Tools
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