Error Code P0342 is defined as Camshaft Position Sensor “A” Circuit Low. This means the CMP (camshaft position) sensor circuit on engine bank 1 sends an irregular reading.

It’s a generic trouble code, meaning it applies to all vehicles equipped with OBD-II, particularly vehicles made since 1996 up to present. Specifications on the definition, troubleshooting and repairs of course, vary from one make and/or model to another.

Definition

The CMP works by sending signal to the PCM (powertrain control module, also known as ECM or engine control module in other vehicle makes) regarding its position based on how the ‘teeth’ or notches on the camshaft interrupt its magnetic field. The PCM then uses this data to provide the right strategies for the fuel delivery and ignition timing of the engine.

If the input is too lower than the specified range by the manufacturer, or otherwise incorrect, the PCM will not have the right amount of information to provide the proper timing for such functions.

For this instance, the Error Code P0342 suggests that the sensor signals are too low, or not strong enough, making it vague and difficult to interpret. Also, the code refers to the bank 1 “A” sensor, which is located on the side of the engine that contains cylinder 1.

Common Symptoms

The Check Engine light will obviously be activated. Aside from that, the usual symptoms for Error Code P0342 would be:

  • Lack of power
  • Engine misfire
  • Engine hesitation
  • Engine stall
  • Hard starting

Possible Causes

There are many factors that may cause this error code, some of the most common possible causes are:

  • Weak or dead battery
  • Defective starter motor
  • Open or shorted CMP sensor wiring harness
  • Problem in starting system circuit
  • Defective CMP sensor
  • Poor wiring to the starter
  • Bad electrical connections

How to Check

As with other trouble codes, mechanics diagnose this trouble code using an OBD-II scanner. They identify all the codes present and then conduct a visual inspection of the circuitry and wirings in the system.

They will have to make the necessary repairs before clearing the codes and then take the vehicle for a test drive and retest the system.

If there are no problems on the connections or the wirings, and the repairs don’t solve the issue, the technicians will then turn their attention to the battery. They will check the charge of the battery and then test the starter motor. After which, they will retest the system until the problem is solved.

How to Fix

Repairs for Error Code P0342 are usually simple and straightforward, but that is if the problem is resolved on a timely manner. Some of the most common repairs include:

  • Recharging or replacing the battery
  • Repairing or replacing any faulty connectors or wirings
  • Repairing or replacing starter motor
  • Replacing defective CMP sensor

Any problems that cause the engine to be erratic and unpredictable should be taken seriously. A misfiring engine, engine hesitation, or an engine without enough power can be extremely dangerous under certain driving conditions. Also, if left unsolved for long periods of time, poor engine performance can lead to more serious engine trouble.

The most common mistake with this error code is not misdiagnosis, but rather the use of inferior replacement components. Should you need a replacement for the sensor, it is always best to stay away from discounted or any products of questionable quality and use only original equipment manufacturer (OEM) parts.