abs/asr

Hello everyone;
We have a 1992 500sl that we replace the receiver drier as part of installing a reman
compressor. We removed the ABS unit to get
at the drier. There was no intitial problem
with the ABS. We have not been able to get
fluid from the SR bleed port or either rear
wheels at the ABS unit or the calipers. There are no codes present. The front bled
fine and the car drives, but no pressure to
the rear brakes. We have no scanner here but
other shops have suggested bleeding methods without using a scanner and they have not been successful because they all assume you can get fluid from the SR port and rear wheels from the get go. Any ideas? Please
E-mail or call 425 348-4110 collect.
Thanks for your time.
Mike