KlaroFault codeP0337
SEVERECrankshaft Position Sensor A Circuit Low Input
What this code means
Crankshaft Position Sensor A Circuit Low Input.
P0337 is a generic code: it means the same thing on every make. P0337 belongs to family P03xx — Ignition and misfire. Its page explains how to read a code and groups all its codes by part.
Type of fault
The control unit reads a voltage on this circuit below its expected range. Usual causes: a wire shorted to ground or broken, a corroded or loose connector, or the component itself. Check the wiring and connector before replacing the part — that is where many of these faults turn out to be.
Crankshaft position sensor (engine speed)
The crankshaft sensor faces a toothed wheel on the crankshaft or flywheel and counts its teeth as they pass. From that signal the control unit knows the engine speed and the exact position of the pistons: it is the reference for all ignition and injection timing.
What you notice
Without this signal the engine cannot run. A failing sensor typically causes a sudden stall, often when hot, or an engine that cranks but will not start; the rev counter may drop to zero while driving.
How to check it
Look at the connector and the wiring near the gearbox or the crankshaft pulley, where it is exposed to heat and dirt. Clean metal debris off the sensor tip, and check the toothed wheel for missing or damaged teeth. If the engine still runs, Klaro's rev reading dropping out at the moment of a stutter is a strong clue.
Watch it live in Klaro
With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:
- Engine RPM
- Timing advance
What to do
Have it checked promptly. A misfire sends unburnt fuel into the exhaust and destroys the catalytic converter within a few dozen kilometres. If the light is flashing, stop driving.
Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →
How to read this code
- PPowertrain
- 0standardised code
- 3Ignition and misfire
- 37P0337
Other codes for the same part
- P0320Ignition/Distributor Engine Speed Input Circuit Malfunction
- P0321Ignition/Distributor Engine Speed Input Circuit Range/Performance
- P0322Ignition/Distributor Engine Speed Input Circuit No Signal
- P0323Ignition/Distributor Engine Speed Input Circuit Intermittent
- P0335Crankshaft Position Sensor A Circuit Malfunction
- P0336Crankshaft Position Sensor A Circuit Range/Performance
- P0338Crankshaft Position Sensor A Circuit High Input
- P0339Crankshaft Position Sensor A Circuit Intermittent
- P0370Timing Reference High Resolution Signal A Malfunction
- P0371Timing Reference High Resolution Signal A Too Many Pulses
- P0372Timing Reference High Resolution Signal A Too Few Pulses
- P0373Timing Reference High Resolution Signal A Intermittent/Erratic Pulses
