DOBD DashX Browse all codes Blog
P0338

Crankshaft Position Sensor A Circuit High

Ignition / engine position Generic OBD-II High

What it means

P0338 means the crankshaft position sensor "A" signal is reading abnormally high. The ECM relies on this sensor to track crankshaft speed and position for spark and fuel timing, so a bad signal can cause hard starting, stalling, or a no-start, making this a fault worth addressing quickly.

High

Can I keep driving? Risky — the crankshaft sensor is essential for spark and fuel timing, so the engine may stall, run rough, or fail to restart. Fix it before relying on the car.

Real-world scan data

Seen in
28
scans in the past year
Found in
<0.1%
of scans
<0.1%
of scans that found faults

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Common causes

Most likely first

  1. Failed crankshaft position sensor
  2. Damaged wiring or a short to voltage in the sensor circuit
  3. Corroded or loose connector at the sensor
  4. Air-gap or reluctor-ring/tone-wheel damage
  5. ECM fault (rare)

How to diagnose & fix

Work through it in order

  1. Read freeze-frame data and note whether the fault is constant or intermittent.
  2. Inspect the sensor connector and wiring for damage, chafing, or corrosion.
  3. Check the circuit for a short to voltage and confirm correct reference/ground.
  4. Verify the sensor air gap and inspect the reluctor ring for damaged teeth.
  5. Replace the crankshaft position sensor if it tests faulty; clear and re-test.

FAQ

Quick answers

Is it safe to drive with P0338?+
Not recommended. A failing crankshaft sensor can cause a sudden stall, so have it repaired before depending on the vehicle.
Can I just clear P0338?+
It will return as soon as the ECM sees the faulty signal again. The sensor or wiring must be repaired first.

Related codes

Read & clear P0338 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play
Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX