Brake Junction Block
A junction block is used on vehicles that are not equipped with Anti-lock Brakes (ABS). The junction block is located on the left side of the lower radiator support. See Fig 1. The junction block mounts in the same location as the ABS Integrated Control Unit (ICU) does on vehicles with ABS. It has 6 threaded ports to which the brake tubes connect. Two are for the brake tubes coming from the master cylinder. The remaining 4 ports are for the brake tubes going to each brake assembly. The valve is permanently mounted to a bracket which fastens to the lower radiator support. The junction block includes 2 proportioning valves for the rear brakes. One valve is mounted in each end of the block. The proportioning valves are not serviced separately from the junction block.
The junction block distributes the brake fluid coming from the master cylinder primary and secondary ports to the 4 brake tubes leading to the brakes. Since the junction block mounts in the same location as the ABS Integrated Control Unit (ICU), it allows for the common use of brake tubes on the vehicle whether it is equipped with or without ABS. The junction block includes 2 proportioning valves. Placed in the fluid flow passages leading to the rear brake tube ports, they balance front-to-rear braking. See PROPORTIONING VALVE .