Re Engine Brake .. Odd Discovery!

[RobRV]

We bought Our new to Us 1998 DSDP on a Spartan Chassis just over a Year ago.
It has been a delight to drive but the Engine Brake has never felt right to Me. When I flip the Switch On, it certainly caused the Alison to downshift,but unless I was on a really steep hill the only way to accelerate again was to turn the switch off. Otherwise She just seemed to lose power.
Today while trying to locate a blown fuse I happened to pull the Relay for the Engine Brake out of It's socket to make room to extract the Blown Fuse. When I looked at the Relay and the Socket I realized that it had not been installed correctly , in fact the relay was upside down and 1 row over from where it should have been installed. I thought this strange and wondered if that was what might be wrong with the Engine Brake! Sure enough the thing works perfectly now . What really is puzzling is how it Sort of worked in the first place!

[skipwil]

Isn't amazing when you fix one thing it will lead to the other problem getting fixed?
Congratulations on the accomplishment>
Safe Travels...

[RobRV]

So now I have discovered another interesting thing about the "Blown Fuse" ! It was a 5 Amp Fuse which was really "Cooked"! I replaced it with a new one and everything seemed to be normal. The Label for the fuse reads "Aux Brake"
Days later I had occasion to use the Emergency Four Way Flashers. while hooking up the Toad.
Upon exiting the vehicle I walked towards the Rear. I heard what can only be described as an ongoing series of bursts of Air! What is going on?
Removing this Fuse stopped whatever it was that was causing the "Chuffing" sound. But what is it that is wrong here?

[AC eagle]

It might be the air dryer.

[RobRV]

The Noise certainly sounds the same as when the Air dryer releases , the thing is What is causing it to do this over and over again when the fuse is installed but not when the fuse is removed!

Everything seems to work correctly without the fuse and when a fuse is installed the chuffing only occurs when the Four way flashers are turned on!

[RobRV]

Turns out that the socket that I believed to be for a Fuse is actually for a Diode that switches the Brake Lights on when the Engine Brake is switched on! For those of You who don't like this feature simply unplug the Diode!