Technical Description of OBD-II Trouble Code
Intermittent Circuit Issue with Camshaft Position Sensor A (Bank 2)
What does that signify?
This is a generic diagnostic trouble code (DTC) related to the powertrain, which applies to all makes and models manufactured from around 2003 onwards. While this code is more commonly found in Dodge, Chrysler, Ford, Honda, Jeep, BMW, and Acura vehicles, it can affect vehicles of any make. The specific troubleshooting steps will vary depending on the vehicle.
These vehicles may have a single camshaft in the engine block, or a single (SOHC) or dual (DOHC) overhead camshafts. However, this code specifically pertains to the absence of the expected signal from the camshaft position sensor(s) in Bank 1 at certain times. It is an intermittent electrical circuit fault that does not occur constantly. Bank #2 refers to the engine bank that does not contain cylinder #1.
The PCM (Powertrain Control Module) utilizes the Camshaft Position Sensor to determine the accuracy of the Crankshaft Sensor signal, the timing of a given Crankshaft Position Sensor signal in relation to Cylinder #1, and for fuel injector synchronization and start of injection.
Codes P0340 or P0341 may also be present simultaneously with the P0349 code. The only difference between these three codes is the duration of the problem and the specific electrical issue affecting the sensor/circuit/engine controller. Troubleshooting steps may vary depending on the manufacturer, type of camshaft position sensor, and wire colors.
Symptoms
The symptoms associated with an engine code P0349 may include:
Potential Causes
The typical causes for this code are:
Diagnostic and Repair Procedures
A good starting point is always to search for any relevant technical service bulletins (TSBs) pertaining to your specific vehicle. The vehicle manufacturer may have a PCM flash/reprogram available to address this issue, so it is worth checking before embarking on a potentially lengthy and incorrect troubleshooting path.
Next, locate both the Camshaft and Crankshaft Position Sensors in your particular vehicle. Once located, visually inspect the connectors and wiring. Look for any signs of chafing, rubbing, exposed wires, burn marks, or melted plastic. Separate the connectors and carefully examine the terminals (metal parts) inside. Check for signs of corrosion, burning, or a greenish color, which may indicate abnormality. If necessary, you can obtain Electrical Contact cleaner from any auto parts store to clean the terminals. Alternatively, you can use 91% rubbing alcohol and a soft plastic bristle brush for cleaning. After cleaning, allow the terminals to air dry and apply some dielectric silicone compound (the same type used for light bulb sockets and spark plug wires) at the points of contact.
If you have a scan tool, clear the diagnostic trouble codes from the memory and observe if this code reappears. If it does not, then the issue was likely related to the connections.
If the code does reappear, further testing of the sensor and its associated circuits will be necessary. The subsequent steps will depend on the type of sensor you have: Hall Effect or Magnetic Pickup. You can usually determine the type by the number of wires connected to the sensor. If there are 3 wires, it is a Hall Effect sensor. If there are 2 wires, it is a Magnetic Pickup style sensor.
Hall Effect Sensor
If it is a Hall Effect sensor, disconnect the harnesses connected to the Camshaft and Crankshaft Position Sensors. Using a Digital Volt Ohm Meter (DVOM), test the 5V power supply circuit for each sensor to ensure that it is receiving power (Red lead to the 5V power supply circuit, black lead to a good ground). If there is no 5 volts reaching the sensor, repair the wiring between the PCM and the sensor, or consider the possibility of a faulty PCM.
If the power supply circuit is functioning properly, use the DVOM to check if there is 5V on each signal circuit going to each sensor, indicating the presence of a signal circuit (Red lead to the sensor signal circuit, black lead to a good ground). If there is no 5 volts reaching the sensor, repair the wiring between the PCM and the sensor, or consider the possibility of a faulty PCM.
Next, verify that there is a good ground connection at each sensor. Connect a test light to a 12V power source and touch the other end of the test light to the ground circuit for each sensor. If the test light does not illuminate, this indicates a problem with the circuit. If the test light does illuminate, wiggle the wiring harness connected to each sensor to check for any flickering of the test light, which would indicate an intermittent connection.
Magnetic Pickup Style Sensor
If it is a Magnetic Pickup style sensor, you can test the sensor itself to determine if it is functioning correctly. Perform the following tests:
With the sensor disconnected, use an ohmmeter to measure the resistance between the two terminals of the Camshaft / Crankshaft Position Sensor. Compare the measured resistance to the specifications for your vehicle, typically ranging from 750 to 2000 ohms. While still on the ohms setting, disconnect one lead of the ohmmeter from the sensor and connect it to a good ground on the vehicle. If you obtain any resistance reading other than infinite or OL (open loop), it indicates that the sensor has an internal short to ground. Avoid touching the metal part of the leads with your fingers, as this may affect the readings.
Reconnect the two leads of the DVOM to the two terminals of the Camshaft / Crankshaft Position Sensor. Set the meter to read A/C voltage. While cranking the engine, observe the A/C voltage output on the DVOM. Compare the reading to the manufacturer’s specifications for your vehicle. As a general guideline, a reading of approximately 0.5V AC is considered acceptable.
