Jeep Engine Code P0340: (Meaning, Causes & Fixes)

Codes are stored in your Jeep and show up on the monitor when an issue persists with the vehicle. The ‘P’ in the code denotes the powertrain system. The digit 3 represents that there is malfunctioning in the ignition system or misfiring is occurring. The last two digits, 40, show the OBD II Diagnostic Trouble Code. In this case, the DTC shows that a circuit malfunction in bank 1 of the camshaft position sensor ‘A’ has been detected.

What Causes Jeep Code P0340?

Jeep code P0340

Without a proper checkup and thorough investigation, it can be challenging to determine what caused a P0340 error code. However, there are certain causes that you can keep in mind before getting it checked. Here are some potential causes of Jeep code P0340:

  • A damaged camshaft position sensor
  • Defected or dirty reluctor ring on the camshaft.
  • Damaged, corroded, or shorted camshaft position sensor circuit wiring. 
  • A defective, corroded, or shorted camshaft position sensor circuit connector.
  • A broken crankshaft position sensor.
  • An expanded or misaligned timing component.
  • An outdated ECM software.
  • A faulty ECM.
  • A damaged Powertrain Control Module (PCM).

Any one of these reasons could be causing the P0340 code to show up. In any case, you will need to get it diagnosed and checked by a professional. Otherwise, it could be quite dangerous. 

Symptoms of Jeep Code P0340

Here are the symptoms that you need to be aware of when thinking about the P0340 code:

  • The check engine light turns on.
  • The Jeep doesn’t start or starts with difficulty.
  • Lack of power while driving.
  • The engine misfires. 
  • Rough idling and stalling. 
  • The motor runs with double values. 
  • Jerking when the vehicle accelerates. 

If either of these symptoms is showing up in your Jeep, it could be a sign of the P0340 code. If you are unsure whether these are just minor faults or a symptom of error code P0340, then head straight to a professional mechanic and get your Jeep checked. 

How Serious is the P0340 Code?

Any issue can be dangerous for you and your car, especially driving. However, the P0340 code is considered to be severe. If you continue to ignore this issue, it could seriously damage your car. 

If you’re driving while the P0340 code is showing up, it could lead to an accident in the engine, making it highly unsafe to operate the vehicle. Therefore, diagnosing the code and resolving it as soon as possible is critical. 

How to Fix the P0340 Error Code

How to Fix Jeep Engine Error Codes

The first thing you need to do when there is a fault in the camshaft position sensor is diagnose the issue. Once the cause is known, you can move ahead to fix it. Here are some steps to guide you through the process:

Step 1:

Carefully check the camshaft position sensor plug for any faults. First, disconnect the connector, then check the sensor and connector from the engine wiring equipment. Look for signs of water ingress, oxidation, and damaged pins. 

When the plug is disconnected from the camshaft sensor, it can be checked with a multimeter. Check for resistance in the sensor. A high value denotes a defective sensor. 

Step 2:

In some cases, the sensor is damaged. The sensor is partly placed in the cylinder head. Due to continuous pressure and heat in the cylinder, the sensor’s plastic may become porous, causing the sensor to break inside. 

Sometimes, the cable connections of the sensor can be damaged as well. You can also replace the sensor at home if you have some mechanical knowledge. After replacement, you can delete the error memory. 

Step 3:

If you have replaced the camshaft sensor and the code is still showing up, you should look at the encoder wheel on the camshaft. Any damage could have caused incorrect measuring values by the sensor. 

Diagnosing and Clearing the P0340 Error Code

Using an OBD II scanner, you can easily find the fault within your vehicle. You can also come across additional information regarding the DTC and understand how serious the problem is. 

After fixing the issue or replacing the camshaft sensor, you can clear the error memory and other fault codes. 

Common Errors While Diagnosing the P0340 Error Code

When the P0340 code shows up, there are some common mistakes that people end up making while trying to diagnose and resolve the issue. 

First, people tend to look into each issue highlighted by the OBD II scanner and fix them individually. What you need is a holistic approach. 

Before understanding the P0340 code, you should understand the interrelationship with the OBD II scanner system. By doing so, you will not only find the root cause of the issue, but you can also come up with the perfect solution. 

Often, people are quick to replace the camshaft position sensor when the P0340 code occurs. If there is a defect in the wiring or connections, it goes unnoticed. Hence, the CMP sensor isn’t the only component you need to look at. 


Can I drive with a P0340 code?

If the code shows up, there’s an electrical issue within the camshaft position sensor. This directly affects the engine and valve timing. Hence, driving with a P0340 code is not recommended since it could drastically damage the engine and other components. 

How much does it cost to fix a P0340 code?

Fixing the P0340 code can cost anywhere between $75 to $200, depending on the labor cost and the price of parts you might need to change. A dirt cleanup inside the connector will only cost a few bucks, but if you’re changing the sensor, it will end up costing more. 

Does the P0340 code clear itself?

No, the P0340 code doesn’t clear up itself. The check engine light will still be on when you replace a faulty sensor. The P0340 DTC will be stored in the diagnostic memory. Hence, you need to clear the memory, so there is no confusion in future repairs. 

Does the P0340 code cause a no-start?

Sometimes, the P0340 error code stops the vehicle from starting. If the valve timing is affected, the engine doesn’t get enough air to start. At times pressing the throttle hard may resolve the issue, but it isn’t recommended. 

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Whenever there is a malfunction in the camshaft position sensor, the P0340 code will show up. If the code stays on, it will affect the engine adversely. So whenever you see this code in your Jeep, you need to hire or contact a professional mechanic to diagnose and resolve the issue. 

Depending on the issue, the cause may not be quite serious, or you may have to change the sensor altogether. However, you can avoid this issue if you check your Jeep regularly. So, rather than ending up with a troublesome code, get your vehicle maintenance and repairs, and most importantly, drive safe!

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