P0343 Camshaft Position Sensor ‘A’ Circuit High Input

Fault code P0343 camshaft position sensor ‘A’ circuit high input is related to the engine timing input signal to ECU. Camshaft position sensor is a electromagnetic sensor. Monitor the rotation of camshaft and it each teath send the signal to ECU. Engine control module receive these signal from cam sensor and calculate the proper amount of fuel injection in combustion cylinder. Fault code P0343 camshaft position sensor ‘A’ circuit high input store in ECU can lead the engine to not start.

Engine control module monitor the signal of camshaft rotation in the form voltage. If there is any problem with camshaft rotation or its teath gas the signal voltage may be vary. Voltage difference in the signal can creat the fault code P0343. And when this fault code is store in the engine control module it can cause the engine to not start or it can take long crank to start the engine.

How serious is fault code P0343 :

Fault code P0343 is related to camshaft position sensor input signal which is responsible for engine starting. Fault code P0343 is set at failure camshaft sensor or mechanical problem with engine. Untill this fault code will store in engine control module there is low responsibility for starting of engine.

Cause of P0343 camshaft position sensor ‘A’ circuit high input :

  • Faulty electromagnetic camshaft sensor.
  • wrong engine timing.
  • Broken engine chain or belt.
  • Broken teath of camshaft.
  • Damage wiring harness of sensor.

Symptoms of P0343 camshaft position sensor ‘A’ circuit high input :

  • Faulty cam shaft sensor will creat problem in engine starting.
  • Hesitation in engine.
  • Loss of power while driving.
  • High fuel consumption or low mileage.
  • Fault code will store in engine control module.

Solution of P0343 camshaft position sensor ‘A’ circuit high input :

  • Replace faulty electromagnetic sensor.
  • Set proper engine timing.
  • Replace or repair engine timing chain.
  • Repair damage wiring harness sensor.

Tool require to diagnose :

  • Scane tool to scane the fault code present in ECU.
  • Multimeter to check the power supply of camshaft sensor.
  • Scope to monitor the signal of camshaft sensor.
  • To box to remove or installing of sensor.

How to solve Fault code P0343 :

  • Mechanic should start diagnosing of this trouble code from scaning the fault code,if it is in history or permanent status. Permanent fault code will never delet until the problem is solve which creat fault code.
  • Check the power supply of camshaft sensor.
  • Connect the scope to camshaft sensor an monitor the signal of sensor.
  • Check If the output signal of sensor is matching the actual graph of sensor signal .
  • Check the engine timing, broken timing chain or belt, broken teath of camshaft sensor.

Special note :

Before replacing camshaft sensor check wiring harness of sensor and power to the sensor. Damage wiring harness or mechanical problem inside the engine control module can also be the reason behind trouble code P0343. So before replacing sensor check the power supply, monitor signal of sensor and check mechanical fault of engine.

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