HP 9122D Service Manual page 27

TROUBLESHOOTING
If one drive fails then replace the failing drive mechanism.
If both drives fail, then perform Test 14.
If test 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.
If INIT fails, it is possible that either the drive or controller/power peA cquld cause the
failure.
If disc access light comes on then perform Test 14
If Test fails then adjust the PLL per procedure on page 4-14
If the PLL adjustment does not correct the problem or cannot be made, then replace
the drive
If drive replacement does not correct the problem, then replace the original drive
In
the 91225 and change the controller/power PCA.
If disc access light did not come on, replace the controller first; if failure persists, replace
original controller and change the drive mechanism. -
If 55/80 Exerciser is not available perform the following:
1. If a computer which supports the 9122 is available, attempt to INITIALIZE or FORMAT using
appropriate host commands on each drive. (This tests the read/write capability of the drive and
the controller/power PCA.)
If disc access light comes on,the HP 9122 I/O circuitry is good. If it does not come on,
replace the controller/power peA
If one drive fails then replace the failing drive mechanism
If both drives fail then perform Test 14.
If test 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 peA.
If disc access light comes on the 9122 I/O circuitry is good
If disc access light does not come on then replace the controller/power peA
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