IBM PCjr Hardware Maintenance And Service page 75

I
4. Perform advanced POST.
The system board is bad. Replace it.
Reattach the original 64KiB memory and
display expansion if you previously replaced it.
Repeat advanced POST and the advanced
tests to ensure that the IBM PCyr is operating
correctly.
The problem has been corrected. Repeat
advanced POST and the advanced tests to
ensure that the IBM VCjr is operating
correctly.
Memory 3-200-9