Got a problem at the min can’t build any air and the signal pipe has air in it thus holding the compressor open , Edit Daf air dryer down by the 2nd steer nice place to put it 
water in the circuit board making the plunger hydraulic or stick in freezing weather ,yet there’s no units in the country for 6weeks yet .quick blow out and re seal let’s see …
Been having suspension control unit problems this last week in the cold weather. Am presuming there is dampness somewhere, preventing a solenoid from operating. It is intermittent so I’m hoping it clears.
When I was young, some of the little fishing boats here had KELVIN, petrol paraffin engines with magnetos for ignition. Every now and again, some of the old guys would take the mag off, take it home and leave it in a low oven overnight. “Just to be sure” as they would say.
Well it’s not worked 
apparently there’s umpteen Dafs like this and when in 6 weeks time those air dryers arrive in the U.K. they are already spoken for 
so I’am borrowing a 2nd hand one and flashing the code across