3406b Jake Problem

Hello,
I have tried doing some research and haven't found exactly what I am looking for. We have an 89 International 9300 with a 3406B CAT. The jakes work well on all 3 stages but sometimes when you let off on the throttle nothing happens. I find if I bump the throttle a few times it will come on. I figured there was a switch in the foot pedal like there is on the clutch but I did not see anything.

Anyone have any ideas? Maybe I'm wrong, but seems like when I first start driving everything works fine, and later as it gets warmed up it starts acting up.

Thanks

 

I checked for dirt under the pedal, cleaned it all up and didnt fix the issue. I found the 2 terminal switch behind the fuel shut off on injection pump. Had two wires with spades on them. Took them off and cleaned them, crimped the ends down some more for a tighter fix. Did not fix the issue. Could the switch there be bad?