POST CODES display the last known success, not the current failure.
Putting aside this particular motherboard BIOS, readers should be aware that some 'POST code' information sources are wrong/misleading. For example, the "IBM AT BIOS:" table at the bioscentral.com web site. Let's pick a line in that table, e.g. POST code 08. 08 is described there as, "DMA page register tested". That is wrong. A look in IBM's published source code for IBM AT's motherboard BIOS reveals the 08 test as:
Step 1: Output the POST code of 08.
Step 2: Test the DMA page register.
Step 3: If the test fails, halt the CPU.
So, on my IBM AT (with IBM BIOS ROM's), if 08 was the last POST code shown on my POST card, the DMA page register test failed. bioscentral.com's "DMA page register tested" would very much mislead me. Instead it should be something like, "Starting test of DMA page register."
Also, bioscentral.com does not show that during the lifetime of the IBM AT, IBM changed the order of two of the tests. (See [
here].)
Short descriptions like "RAM refresh" can be misleading. The IBM BIOS for the IBM AT tests only
part of RAM refresh.