What does P0335 mean?

The ECU does not get a valid signal from the crankshaft position sensor.

Why does P0335 cause a no-start?

The ECU needs crankshaft speed and position to time spark and fuel; without it, the engine usually won't start.

Engine sensors

P0335 — Crankshaft Position Sensor A Circuit

The ECU receives no signal or an invalid signal from the crankshaft position sensor. This sensor tells the ECU engine speed and piston position, so without it the engine may not start.

Severity: High

Common causes

Faulty crankshaft position sensor
Damaged wiring, connector or harness
Damaged or contaminated reluctor ring/tone wheel
Incorrect air gap or loose sensor
Failing battery or low voltage

Symptoms

Engine cranks but does not start
Stalling while driving
Intermittent hard starting
Tachometer not working, check engine light

How to check

Inspect the sensor connector, wiring and mounting
Check the signal with a scope or scan tool while cranking
Inspect the tone wheel for damage or metal debris
Replace the sensor if the circuit and wheel are fine

Can you keep driving?

Not recommended: the engine can stall without warning, including in traffic. Repair it before driving.

Frequently asked questions

What does P0335 mean?: The ECU does not get a valid signal from the crankshaft position sensor.
Why does P0335 cause a no-start?: The ECU needs crankshaft speed and position to time spark and fuel; without it, the engine usually won't start.

General reference information. It does not replace a diagnosis on your own vehicle. The same code can have different causes depending on make, model year and engine; check the manufacturer's documentation or ask a technician with a scan tool.