Camshaft Position Sensor A Circuit High (Bank 1 or Single Sensor)
The P0343 code means the vehicle's onboard diagnostic system has detected: Camshaft Position Sensor A Circuit High (Bank 1 or Single Sensor). This is a critical severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- moderate
- Estimated cost
- $80 - $300 (parts and labor)
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What Are the Symptoms of P0343?
- Engine cranks with extended start time
- Engine stalls without warning
- Check Engine Light illuminated
- Rough idle and misfires
- No-start condition in some cases
What Causes P0343? (Most Likely First)
- Open circuit in CMP sensor ground wire Very High
- Faulty camshaft position sensor (open coil) High
- Short to voltage in CMP sensor signal wire High
- Disconnected or corroded sensor connector Moderate
- PCM input circuit fault Low
Can I Still Drive with P0343?
Short distances only. P0343 is rated critical severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
Can I drive with code P0343?
You can drive short distances if the engine runs. Some vehicles will still start using the CKP sensor alone, but fuel injection sequencing will be impaired, causing rough running.
Will the engine start without the CMP sensor?
Many vehicles can start without a CMP signal by defaulting to batch-fire injection using only the CKP sensor. However, performance will be poor and the engine will run rough.
Can a bad CMP sensor damage the engine?
A bad CMP sensor itself will not damage the engine. However, the poor running conditions it causes (misfires, improper fuel timing) can damage the catalytic converter over time.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P0343?
-
Check CMP sensor signal -- a constantly high voltage reading confirms the fault
-
Test continuity of the sensor ground wire from connector to PCM
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Check for short to voltage in the signal wire with sensor disconnected
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Inspect the connector for loose, corroded, or pushed-back pins
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Measure sensor resistance -- an open reading (OL) confirms internal failure
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
P0343 on Diesel, EV & Equipment
The same code ID appears across other engines and platforms. The diagnostic flow varies by manufacturer — these are the platform-specific breakdowns:
Which Vehicles Commonly Get P0343?
- 2007-2017 Honda Civic
- 2008-2018 Toyota RAV4
- 2005-2015 Ford F-150
- 2010-2020 Chevrolet Silverado
- 2009-2019 Hyundai Sonata
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