The Hella oil level sensor, often requiring VCDS for diagnostics, is a sophisticated component utilizing ultrasonic technology for accurate oil level measurement. This sensor incorporates an onboard computer, an Application Specific Integrated Circuit (ASIC), and integrated ultrasonic and temperature sensors within a single multi-chip module. This complex architecture contributes to the sensor’s resilience against shock and vibration.
The oil level sensor operates by emitting an ultrasonic signal that reflects off the oil’s surface. By measuring the signal’s transit time and considering the speed of sound within the oil, the sensor calculates the oil level. A damping cup, with openings at its base and tip, ensures a consistent oil flow and minimizes fluctuations in the dynamic range, facilitating accurate measurements.
While VCDS can be used to diagnose issues, directly disabling the oil level sensor via VCDS coding may not be possible. Verification of sensor functionality relies on analyzing the signal transmitted to the control unit. Using an oscilloscope to examine the signal at the signal line (point A) can indicate signal transmission, but it doesn’t provide a definitive assessment of the sensor’s overall health. The displayed waveform encompasses both temperature and level information, making interpretation complex.
Therefore, bypassing the sensor would require replicating the “good” signal read by an oscilloscope with a custom circuit. This workaround, however, might lead to the loss of oil temperature data due to the composite nature of the sensor’s signal. The intricate design of the Hella oil level sensor highlights the challenges in manipulating its functionality and underscores the importance of proper diagnostics using tools like VCDS.
