HP 9122D Service Manual page 28

TROCBLESHOOTISG
If INITIALIZE/FOR\IAT fails, it is possible that either the drive or controller/power PCA
could cause the
failure~.
If disc a,ccess light comes on then perform Test 14.
If test fails then adjust the PLL per procedure on page 4-14
IF PLL adjustment does not correct problem or cannot be made, then replace the drive.
If failure persists, replace original drive in the 91225 and change the controller/power
PCA.
If disc a,ccess li:sht did not come on, replace the power/controller PCA first; if failure per-
sists, replace anginal controller and change the drive mechanism.
2. If no host computer is available: (This could occur if a drive -has failed and it is not possible to
boot the computer.)
91220
----
Perform Tests 1.2 and 13
If vne drive fails then replace the failing drive mechanism.
If both drives fail, then perform test 14.
If Te:st 14 fails then adjust the PLL per procedure on page 4-14.
If PLL adjustment does not correct the problem or cannot be made, then replace the
controller/power PCA.
Pe rf orm Test 1 4
If test fa.ils then adjust the PLL per procedure on page 4-14.
If PLL adjustment does not correct the problem or cannot be made, then replace the
controller/power PCA.
If Test 14 passes then perform Test 12.
If Test 12 fails, then replace the drive;
if
failure persists, then replace orginal drive and
repla.ce power/controller PCA in 91225.
If Test 12 passes, replace power/controller peA; if failure persists, then replace original
powe:r/controller PCA and replace drive.
PROCEDURE P4 (Occasional or Intermittent failures)
Some causes of this type of problem include the following:
• Media problems; see information in "General" section.
4-10