replaced corroded line. ABS & break light on cannot bleed rear brakes. on 1993 Chevrolet G Series Van (G20)

pedal goes all the way down but flied not coming out nether rear bleeders

Asked by for the 1993 Chevrolet G Series Van (G20)
2 answers
Remove bleeder screws and clean. If bleeders are open,may have to vacuum bleed.
at times the proportion valve sticks close rear bleeders and hit the brake pedal hard then open rear bleeders and let it gravity bleed for 15 min