Womo Fiat Ducato 280 does not start, does not indicate any pregloss

Hello your experienced screwdriver and lover of the Duc, have a Duc 280 which shows no pre-glow when switching on the ignition. Since it also does not start I assume that it does not. If I pull the air hose of the suction bridge and admit during the start process cold start aid, the Duc also immediately blows off and shows power (starts immediately ) . I suspect a defect at the pre-glow system or missing compression. I am not a savvy screw he (so only basic knowledge ) , but my baby wants to “doctate ” himself to be better able to deal with problems . So if someone here has a real idea what I’m going to do , I would appreciate help very much . Also I ask to give only serious advice , because my time is relatively limited thanks to work . So a checklist would be really great . I am already curious , how easy this will be for some of you !