P0392 indicates the Powertrain Control Module (PCM) detected an abnormally low voltage signal from the Camshaft Position (CMP) Sensor B on Bank 2 (the engine bank not containing cylinder #1). This sensor monitors camshaft position to synchronize fuel injection and ignition timing.
The sensor itself has failed internally, producing an open circuit or an output voltage below the acceptable range.
Damaged, chafed, or shorted wiring between the sensor and PCM, or corroded/water-damaged connector pins on Bank 2 sensor circuit.
Loose, oxidized, or spread connector pins causing high resistance or intermittent signal loss.
Damage, contamination, or missing teeth on the camshaft timing gear trigger wheel can prevent proper sensor signal generation.
A jumped timing chain or belt can misalign the camshaft position relative to the crankshaft, causing abnormal sensor readings.
Rarely, the PCM may have an internal circuit failure affecting the Bank 2 CMP sensor input. This should be a last resort after all other causes are ruled out.
Driving is not recommended. The engine may run poorly, misfire, or fail to start entirely. Prolonged operation with incorrect camshaft timing can cause catalytic converter damage.
No. P0391 is 'Camshaft Position Sensor B Circuit High Bank 2,' indicating excessive voltage, while P0392 indicates insufficient/low voltage signal.
Almost never. The PCM is the least likely cause. Shops that automatically recommend PCM replacement for P0392 are misdiagnosing the issue. The sensor, wiring, or connections are the actual problem in the vast majority of cases.
Repair costs vary significantly by vehicle and which component is faulty. Sensor replacement typically costs less than diagnosing and repairing wiring issues or timing problems.