Eagle DDEC2 Jake Switch Not working

[homermandy]

Any idea how to troubleshoot why the jake switch does not activate the jakes all of a sudden?  Never had an issue with it before. I did check the 2 speed jack switch at the dash and there is NOT 12V to the switch, so I assume that is part of the problem.  It is wire#113,#114, and #115(red,white,and blue). Looks like the harness goes directly to the rear of the bus as it does not actually connect to the circuit breakers up front.  Any ideas? Thanks

[H3Jim]

When my jake was not working, it was the throttle sensor in the pedal.  It was not telling the electronic controls that the throttle was fully off, a requirement for the Jake to turn on.

[busguy01]

Haven't looked at one in awhile but I think it switches the ground not the hot.