P0343 OBD-II Trouble Code: Camshaft Position Sensor Circuit High Input


SCHEDULE P0343 DIAGNOSTIC Get a fair and transparent estimate upfront

Cost of diagnosing the P0343 code

P0343 is a diagnostic trouble code (DTC) for "Camshaft Position Sensor Circuit High Input". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $79.99. Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.00 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
SCHEDULE P0343 DIAGNOSTIC Get a fair and transparent estimate upfront

check engine light

P0343 trouble code definition

A P0343 trouble code is related to a vehicle’s timing system and the camshaft position sensor that monitors the rotation of the camshaft to relay data to the engine computer so it can calculate the appropriate amount of fuel and ignition.

What the P0343 code means

P0343 is an OBD-II generic code for a voltage problem with the camshaft position sensor. This is a fixed electromagnetic sensor that’s connected to a rotating part on the camshaft that records the position of the “teeth” to indicate the stroke of each piston so the computer can apply the appropriate fuel and spark. The position of the camshaft creates various gaps between the sensor which change the magnetic field to change the voltage from the sensor. When a P0343 is present, that voltage is not within the manufacturer’s parameters. It also applies to the bank 1 sensor that monitors cylinder 1.

What causes the P0343 code?

Usually, the camshaft position sensor has been fouled from oil or moisture, causing a bad ground or voltage in the signal wiring. However, other likely causes include:

  • Faulty camshaft position sensor
  • Faulty ground wiring
  • Faulty power wiring
  • Faulty starter motor
  • Weak or dead battery
  • Faulty engine computer

What are the symptoms of the P0343 code?

Because a faulty camshaft position sensor can cause the engine computer to supply the incorrect amount of fuel and or spark, it’s likely that you’ll encounter poor driving conditions with a P0343. It’s typical for the code to result in bucking, surging, stalling or inconsistent starting issues.

How does a mechanic diagnose the P0343 code?

Your mechanic will start with a visual inspection of the sensor to determine if it’s being fouled from an oil leak or frayed/damaged wiring. It is possible to clean a sensor enough for it to work as it should. Electrical contact cleaner or rubbing alcohol can help in cleaning and your mechanic will likely clear the code to see if it returns. If it does, the sensor itself is likely the culprit. This can be tested with a multimeter and a test light to determine if it’s getting the voltage supply it needs. If not, your mechanic will likely replace the sensor with a high-quality replacement part, clear the code and test drive to ensure the new sensor works.

Common mistakes when diagnosing the P0343 code

The most common mistake when dealing with a P0343 circles around bad replacement sensors. It’s important to use high-quality replacement parts and avoid cheaper or used variants. Because some sensors will also be fouled due to oil leaks, it’s recommended to have any near-by leaks repaired so the problem doesn’t persist.

How serious is the P0343 code?

Because the camshaft position sensor is so critical for a modern vehicle’s fuel injection, a P0343 can severely affect the way a vehicle drives. It’s wise to address this code as quickly as you can.

What repairs can fix the P0343 code?

The most common repairs for a P0343 are as follows:

Additional comments for consideration regarding the P0343 code

P0343 codes seem to be prominent with Chevrolet, Kia, Volkswagen and Hyundai models - typically around the model years 2003 to 2005. It’s also not too uncommon for a P0343 code to trigger additional trouble codes as a result.

Need help with a P0343 code?


trouble codes
Check Engine Light


Get a fair and transparent estimate upfront

Recent Check Engine Light is on Inspection reviews

Excellent Rating

YourMechanic Check Engine Light is on Inspection Service

Average Rating


Number of Reviews


Rating Summary


39 years of experience
1020 reviews
39 years of experience
Lexus LS430 - Check Engine Light is on - Houston, Texas
I was very pleased with the courtesy and work of Mr. Smith. He was exceptional in explaining and correcting the problem and thereby gained my trustI . I request he be my mechanic in all future service requests. I had a great experience working with Mr. Ben Smith.


19 years of experience
203 reviews
19 years of experience
Ram ProMaster 1500 - Check Engine Light is on - Bonita Springs, Florida
Prompt, polite and personal. Took the time to explain the process and his recommendations. 2 thumbs up


23 years of experience
37 reviews
23 years of experience
Ford F-150 - Check Engine Light is on - Federal Way, Washington
Very helpful and explained everything and what needs to be addressed. I feel informed and confident in Mike’s assessment and look forward to him performing services on my vehicle.


9 years of experience
650 reviews
9 years of experience
Honda Civic - Check Engine Light is on - Chicago, Illinois
Rigoberto came on time & quickly diagnosed the problem- rats chewed thru wiring near the battery. He wasn’t able to fix it himself bc of parts, but gave me recommendations on where to go & how to not have the dealership sell me services that are not needed.

More related articles

The Traveler’s Guide to Driving in Malaysia
How to Get a Louisiana Driver's Permit

Related questions

Q: Vehicle shuts off intermittently at idle


Q: Can a bad canister purge valve cause my car to shake/vibrate under the hood when i brake or make constant stops?

First thing to check is the problem codes that are setting your Check Engine light on. While it is true that fumes from the vapor canister are pulled into the engine during "coast down" when there is high vacuum in...

Q: Camshaft position sensor error code P0343

Hello. The P0343 code indicates there is no signal from the passenger side cam position sensor (Bank 1 actually). Given you have changed the sensor, this would suggest a wiring or connector issue. Your mileage would also make me anxious...

How can we help?


1-800-701-6230 · hi@yourmechanic.com