Crankshaft Position Sensor A Circuit Low
The P0337 code means the vehicle's onboard diagnostic system has detected: Crankshaft Position Sensor A Circuit Low. This is a critical severity code.
- Keep driving?
- No — stop driving
- DIY difficulty
- moderate
- Estimated cost
- $80 - $350 (parts and labor)
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Common Symptoms
- Engine cranks but will not start
- Engine stalls suddenly
- Tachometer drops to zero
- Check Engine Light illuminated
- No spark or fuel injection
Probable Causes (Ranked by Likelihood)
- Short to ground in CKP sensor signal wiring Very High
- Faulty CKP sensor with internally shorted coil High
- Corroded or damaged CKP sensor connector High
- CKP sensor contaminated with oil or metal debris Moderate
- PCM input circuit failure Low
Frequently Asked Questions
Can I drive with code P0337?
No. A low CKP circuit means the PCM is not receiving a proper engine position signal. The engine may not start or may stall unpredictably.
Can metal debris on the sensor cause P0337?
Yes. The CKP sensor uses a magnet, and metal shavings from the reluctor ring or engine components can accumulate on the sensor tip, disrupting the signal and causing a low reading.
How often should the CKP sensor be replaced?
CKP sensors do not have a standard replacement interval. They typically last the life of the engine. Replace only when faulty, not as preventive maintenance.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Check CKP sensor signal voltage during cranking -- should produce AC voltage; consistently low or zero indicates a fault
-
Test for shorts to ground in the signal wire with the sensor disconnected
-
Inspect the sensor tip for metal debris buildup from the reluctor ring -- clean or replace
-
Check the sensor connector for oil intrusion, corrosion, or damaged pins
-
Measure sensor coil resistance -- compare to manufacturer specification
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)
P0337 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:
Commonly Affected Vehicles
- 2007-2017 Honda Civic
- 2008-2018 Toyota Corolla
- 2005-2015 Ford Focus
- 2010-2020 Nissan Sentra
- 2009-2019 Hyundai Elantra
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