Could this be an electrical problem?

Doubt its the ignition.

One thing with air systems is never assume the leaking valve is the problem. A lot of air valves have their exhaust ports open in their neutral position. It could just as easily be another component leaking or backfeeding into that circuit and the leaking valve was just the easiest place for the air to escape.

 

I have bought that valve separate from the other two.
From my parts house. If I remember right they called it a triple valve.
Right under the fifth wheel where all the grease falls.

 

Suspension dump valves are connected to the leveling valve for the air springs. That valve is the brake actuating valve. The two connected to it are for abs. That is why it is so expensive. It is probably got dirt build up in the exhaust port in the bottom causing it to stick open. The electric part they told you about is the power in and out of the abs valves to the wheel hubs. Just cleaning all that grime off and spraying some brake cleaner up in the exhaust port might luckily fix it.

 

Its been a few years maybe $400 or less.
Took it off and parts house matched it up.
I know the whole thing was expensive.
Truck salvage ?

 

If its your own tractor, take it apart very carefully and clean it, make sure everything is moving freely, reassembly carefully. Nothing to lose

 

Delivered to Creech AFB this morning, easy enough, back into a dock stay in the cab as instructed. Could not have been to interesting, no escort.

 

Does that top air line go to another valve? There should be a quick release valve somewhere (behind the 5th whieel?) and that is what usually fails and vents through that center valve. At least, it's a common problem on Freightliners, and the first instinct is to buy that triple valve assembly, which doesn't solve the problem. You can test by disconnecting that air line from the center ABS valve to the quick release valve. If it vents through the open line instead of the center valve then the center valve isn't the problem. Quick release valves are a lot cheaper that those triple ABS valve assemblies BTW.

I had the same problem coming through the mountains in Oregon a couple of months ago. I had to cage the brakes and ride with the yellow knob out listening to Beeeeeeeeeeeeeep for the next three hours.