I have a cat c12, and my Jacob's brake worked before I had my heat and air worked on behind the dash, my wiring has 3 wires blue, yellow and green in loom from brake switch, through the firewall to motor, none have power to.them with test light, relay is in fuse box but nothing to attach it to on back side of box, and no wires connecting to my clutch switch, any help.would be appreciated thanks
Jacob's brake problem
Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by Brookshire36, Apr 28, 2020.