Auto repair experience


Hyundai Santa Fe stalls, code P0335

On the diagnosis of Santafe, the reason for the appeal is stalling. After that, it starts and drives like nothing happened. After a while it shuts down and starts up again. We connect the scanner, in the memory of the engine ECU, error P0335 is the crankshaft position sensor circuit. We use an oscilloscope to check. We connect the first channel to the Crank Sensor, the second to the Cam Sensor, the third to the signal of the ignition coil of the first cylinder and the fourth to the nozzle of the first cylinder.

The engine runs for half an hour, after which it stalls, we look at what happened, the control of the ignition coil was lost, this can happen if the crankshaft and camshaft signals fail to synchronize. The ECU is simply lost in which cylinder to apply a spark.

Santa Fe stalls P0335

Let's take a closer look at the signals of the Crankshaft Sensor and the Camshaft Sensor and see that the duration of the skip is changing. When the gap is wide, the engine runs normally, as soon as the duration decreases as in the photo, the engine stalls. The ECU does not understand that this is a pass.

Santa Fe Crankshaft Sensor Waveform

The crankshaft position sensor is defective and needs to be replaced only with the original. In these photos, the signal is from a cheap duplicate sensor.