The oil pressure is controlled by the switch mentioned above together with the electronic system in the instrument panel, i.e. the oil pressure is controlled not only by the oil pressure, but also depending on its temperature and engine speed. The following control criteria are valid for control (in Audi cars this means an oil pressure monitoring system):
The engine is not running, i.e. the switch is closed.
The coolant temperature is above 60°C, the engine is running above 1500 rpm and the switch is open.
The coolant temperature is less than 60°C, the engine speed is above 300 rpm and the switch is open.
At engine speeds above 5000 rpm, active oil monitoring is switched off regardless of the position of the indicator lamp switch.
If the switch is open for more than 0.5 seconds with the engine running and engine speed over 1500 rpm, this is remembered. If this effect occurs more than 3 times in a row, the oil pressure control is switched on and does not switch off when the speed drops below 1300 rpm. The count starts again when the ignition is switched on again.
All models listed in this manual have a warning light switch with a pressure limit of 1.4 bar. For identification purposes, the switch is painted black and must only be replaced with the same switch.
What should be done if there are problems with the engine lubrication system?
If the oil pressure warning light comes on while the engine is running or the warning buzzer sounds, turn off the engine as quickly as possible. Do not turn the ignition key to the steering wheel lock position. In this case, you will have to tow the car to the nearest workshop.
If possible, have the oil pressure checked at a workshop, as it is not recommended to restart the engine under these conditions.
The following description concerns the operation check of the oil pressure monitoring system.
Check the oil level and top up if necessary.
Turn on the ignition. The oil pressure indicator light should come on.
If the engine is running with an automatic control system, then the inscription - the indicator "OK" should appear.
Make sure that the oil temperature is around 80°C, i.e. the cooling system fan should turn on at least once.