No communication with the ABS module

Good morning.

You could try removing the valve and cleaning the inside area where it seats. There may be debris on the surface the bleeder mounts.

If that does not work, then the ABS unit will have to be replaced.

Roy

You are welcome. Keep us updated.

Roy

Hello thanks for using 2CarPros, has the brake fluid ever been replaced since you've had the truck? It is a good idea, if the fluid is black in the master cylinder, then bleed the master itself so that none of that old fluid goes into the ABS module, then refill it with new fluid and bleed the whole system. Start with the wheel closest to the master cylinder (so the front drive side) then the passenger side front, then the drivers side rear, and last the passenger side rear, since it's the farthest from the master cylinder. This way all the air will be able to escape. There should also be 2 bleed screws on the abs module, bleed the one closest to the firewall first,then the other.

this guide should help

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

Please run down this guide and report back.

I'm sorry I had the process reversed. Start with the wheel farthest from the master cylinder which is the passenger side rear, then the driver's side rear, then passenger side front, then driver's side front. I'm sorry I had them backwards before, (this is edited) This way all the air will be able to escape. There should also be 2 bleed screws on the ABS module, bleed the one closest, to the firewall first, then the other.

It's just a good idea to flush the brake fluid since you're already replacing the module. It's part of routine maintenance, but also to make sure all the air is out of the new module. Does the new module have bleeder screws on it? Some don't.

Okay, I see. I thought you were replacing the whole hydraulic unit. Yes the modules just bolt right on top of the hydraulic unit. I think this the same module as you're doing in this video . I don't see why you would have to flush the fluid in this case. Unless it's black, that means the seals in the master cylinder are going bad.
https://youtu.be/lUotkKXG9dY

Just make sure the brake pedal is firm and not spongy. That would indicate air in the system. And may I ask who told you to flush the whole system?

No problem, let us know if there's anything else we can help with.