Some time ago I was repairing a damaged 2019 Skoda Karoq with a 1.5 TSI engine, DADA and an installed "04E906455S" valve. The engine module reported the error "21729 - Engine Oil Pressure - P15AA 00 [01100101] - Lower Limit not Reached". In my case, the warning on the Instruments cluster appeared when the oil temperature exceeded 82°C. I browsed many forums on the Internet, which helped me a little, fortunately I found this document, with the help of this document I found out that the engine oil pressure should be around 1.5 Bar. Here is a picture of the valve: Using the VCDS program and interface, I checked the following data: IDE00196 Engine oil temperature IDE00496-ENG188621 Oil pressure switch valve activation-Bits 0-7 IDE02742 Oil pressure actual value IDE11203 Oil pressure setpoint IDE11330 Oil pressure control valve: activation pulse duty factor Here is the engine oil pressure data before the valve replacement: Here is the engine oil pressure data after the valve replacement: Using this data, I found the following, the damaged valve was stuck and remained in the open position, due to low pressure, the electronics are increasingly closing the valve, which is controlled using PWM modulation, the valve closing value is shown by the parameter "IDE11330". Since the engine oil pressure is not reached, the mechanical switch with the parameter "IDE00496-ENG188621" shows the value "0". The engine oil pressure is shown by the parameter IDE02742, the setpoint value of the required pressure is shown by the parameter IDE11203, if the oil pressure drops below the value of 160kPa, a message is generated on the Instruments cluster, which is visible in the picture. Here is a picture of the instrument cluster: I found an explanation of how engine lubrication works on the internet, the valve is used in the system as a safety oil pressure relief valve, in case of LOW oil PRESSURE the valve must CLOSE, in case of EXCESSED oil PRESSURE the valve must OPEN. The mentioned valve is controlled electronically using PWM modulation, thus we can ensure a constant optimal lubricating oil pressure during engine operation, regardless of temperature, oil viscosity and engine speed. Before using this technology, a classic or hydraulic pressure regulation system was used, based on a spring and an anchor which moves and releases pressure at a specific pressure. The solution is simpler, but this classic solution has a flaw, the working pressure can still change when the speed increases or decreases, over the years the spring settles. Here is a rough sketch and explanation of the parts of the engine's lubricating oil system control: As far as I know, such problems and errors can occur for several reasons, these are: - valve failure or damage, - valve or filter mesh clogging on the valve, - excessive oil leakage into other parts of the engine (the cause of the error is not in the valve) - poor pressure or flow of the engine oil pump (the cause of the error is not in the valve) I must warn you, the same valve is used for variable valves, in case of clogging of one of the valves, it is recommended to check both! To help you identify the components on your engine, you can use this page (use a web page translator for easier understanding): https://vwts.ru/articles/engine/engine-1-5-tsi-dada.html