ABS light on C1242 code... what gives?

[hellah fresh]

Hello all! I have a 97 Transport montana and i got a bit of an issue with my rear brakes. So before i had no brakes what so ever and now after i installed a new master cylinder and power bleed the system i only have front brakes. I checked the lines in the rear and no fluid is going to the rear brake lines to bleed out. So now i do have front brakes and no back brakes. What do you think can cause this? i scanned the abs system and here is the code that have come up:


C1286 - ABS Turned on red brake light

C1242 - Rear Esb Does not hold Motor.


And here is a suggestion from another person that i will quote:

"ESB stands for 'expansion spring brake' and it is internal to the abs modulator assembly.
This code is because the piston is slipping in the abs assembly. A common cause for this is
that the motor gear nut has loosened up, and the gear is slipping, therefore not holding the
ESB. The cover underneath the motor pack can be removed, and the nuts on the 3 gears
checked to see if one is loose. It is also possible that the EBCM (electronic brake control
module) is faulty. What needs to be done is have the system hooked up to a scan tool that
can read data and control abs functions to watch voltage numbers and decide what is at
fault"


So he is suspecting the EBCM to go bad. Also i forgot to mention... there is NO power going to the 20A fuse for the ABS solonoid.