Hydraulic Control Unit??

[rmuntz]

A month ago I replaced all brakes, rotors and callipers on my 2011 ram 2500.
When bleeding the brakes the right front wouldn’t bleed unless I turned the truck on. Now I’m having trouble with the right front, again. The brake calliper will press but won’t release. Today I took the calliper off and tried to compress the pistons but they wouldn’t go down.

I don’t fully understand the function of the HCU, but am I correct to understand that there are check valves in it? I know it’s part of the ABS system.

Any insight would be appreciated. Thanks

Ron

 

[04fxdwgi]

Do you have any codes / warnings / CEL on the dash? HCU is not bashful to throw codes.

If the caliper is removed from truck with hydraulic line disconnected and won't bleed down, you need a new caliper. If hydro line is connected and won't bleed down , the flexible lines have been known to deteriorate internally and block flow. The HCU also controls flow.

Start troubleshooting from the cheapest point (calipers and flex lines) to most expensive (very expensive HCU).

HCU controls the anti lock brakes and such.

 

[rmuntz]

Thanks Adam, I've got a new calliper on the way. Let's see how it goes.

 

[rmuntz]

Replaced the calliper, same thing happened. And again, I could not bleed it without starting the truck? With truck running, fluid bled out fine. I have no error codes at all.