P0335
Crankshaft Position Sensor A Circuit
Ignition / engine position
Generic OBD-II
High
What it means
P0335 means the ECM isn't getting a usable signal from the crankshaft position sensor, which it relies on to track engine speed and time ignition and fuel delivery. Because that signal is essential to running, this code can cause hard starting, sudden stalling, or a complete no-start — making it one to address quickly.
High
Can I keep driving? Risky — the ECM needs this signal to fire spark and fuel, so the engine may stall, run erratically, or fail to start at all. Fix before relying on the car.
Common symptoms
What you'll notice
- Check-engine light on
- Hard starting, intermittent stalling, or a no-start
- Engine stumbles or cuts out, often when hot
- Reduced power and hesitation
Common causes
Most likely first
- Failed crankshaft position sensorLikely
- Damaged wiring or a poor connector at the sensorCommon
- Debris, damaged reluctor/tone ring, or misaligned sensorCommon
- Failed engine control module (rare)Less often
How to diagnose & fix
Work through it in order
- Scan for the code and check whether RPM registers on the scan tool while cranking — no RPM points to the sensor or its wiring.
- Inspect the sensor connector and harness for damage, corrosion, or oil contamination.
- Check the sensor mounting and reluctor/tone ring for debris or damage.
- Test the sensor's resistance or signal against spec; replace it if out of range. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0335?+
No. Without a reliable crank signal the engine can stall without warning or refuse to restart, so treat it as urgent.
Can I just clear P0335?+
Clearing it won't help — if the sensor or circuit is faulty the engine may still stall or not start, and the code will return.
Related codes
Often seen with P0335
Read & clear P0335 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX