IBM 5150 Hardware Maintenance Manual page 33

You may have a failing Option Adapter. Follow the procedure
listed below.
1. Position the System Unit Power switch to OFF.
2. Remove one Option Adapter from the System Board (do
not remove the diskette adapter or display adapter until
all other adapters have been removed; remove the display
adapter last).
3. Position the System Unit Power switch to On and check
for the failing symptom.
4. Repeat steps I, 2, and 3 until the failing adapter is located
or all adapters are removed.
DID THE FAILING SYMPTOM REMAIN?
NO
Replace the last device removed. See Section 3,
"Removal/ Replacemen
t."
(Note: Removal of the Display Adapter will
normally result in two sets of one long and two
short beeps. A change in these symptoms to other
~
than two sets of one long and two short "beeps",
did not necessarily resolve the failure.)
YES
020-2