Crankshaft Position Sensor A Circuit High
The P0338 code means the vehicle's onboard diagnostic system has detected: Crankshaft Position Sensor A Circuit High. 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 and will not restart
- Tachometer reads erratically or zero
- Check Engine Light illuminated
- Ignition and fuel injection disabled
Probable Causes (Ranked by Likelihood)
- Open circuit in CKP sensor ground wire Very High
- Short to voltage in CKP sensor signal wire High
- Faulty CKP sensor with open internal coil High
- Disconnected or corroded sensor connector Moderate
- PCM input circuit fault Low
Frequently Asked Questions
Can I drive with code P0338?
No. A high CKP circuit prevents the PCM from properly determining engine position. The engine will not start or will stall unpredictably.
What causes a high CKP circuit?
A high circuit typically results from an open ground wire, an internally open sensor coil, or a short to voltage in the signal wiring. The PCM reads a voltage higher than the expected operating range.
Can I test the CKP sensor at home?
Yes. With a multimeter, measure the sensor coil resistance (should match spec) and check for AC voltage output during cranking. A complete lack of output or an open resistance reading confirms failure.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
-
Check CKP sensor signal with a multimeter during cranking -- excessively high or constant voltage indicates a fault
-
Test for continuity in the sensor ground wire from connector to PCM ground
-
Check for short to voltage in the signal wire -- disconnect the sensor and measure voltage on the signal pin
-
Inspect the sensor connector for pushed-back pins, corrosion, or heat damage
-
Measure sensor coil resistance -- an open reading (OL) confirms internal sensor 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)
Commonly Affected Vehicles
- 2007-2017 Honda Accord
- 2008-2018 Toyota Camry
- 2005-2015 Ford Escape
- 2010-2020 Nissan Rogue
- 2009-2019 Chevrolet Cruze
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