[Beard]

Hello.
in your case, the alternator, oil level sensor, IBS battery sensor and glow plug ECU are all on the same BSD bus.
1. Remove the plug from the oil level sensor and try to measure the oil level.
The oil level is measured with the engine running and with the oil warmed up.
2. Disconnect all BSD bus users except the oil level sensor and measure the oil level.
3. Connect all subscribers of this bus one by one and measure the oil each time.
Snechalo one sensor,
then IBS sensor,
then the generator
then the block of the candle ignition system.
And watch when the oil level changes.
This way you will find which subscriber is messing with your BSD bus.
Or vice versa, turning off each subscriber sequentially one after another, and constantly measuring the oil level.