Had Valley injection in Abbotsford BC. install a BD exhaust brake in 1999. recently I can not hear or feel it engage like it used to. If I open the hood and push the little black rubber thinggy it engages and I can hear it and see it activate. When driving I can turn on the toggle switch in the cab and it dosen't work. The little red light in the toggle switch comes on so I know I have power to the switch but no activation of the brake. Are there any fuses or micro switches on the acelerator pedal that I can check? 
