Troubleshooting Procedures; Fault Isolation Procedures - HP 9122D Service Manual

TROUBLESHOOTING
'Troubleshooting Procedures
This section is divided into Genl!ral information, a troubleshooting flowchart, procedures called out in the
flowchart, and inf 0rmation on i!.terpreting error codes obtained as well as use of the 55/30 Exerciser.
Fault Isolation Procedures
The following procedures will hdp to quickly and accurately
det~rmine
which field replaceable assembly is
defective if a failure occurs.
General Information
• If a flexible disc is damaged
b:r
a drive, inspect the HP 9122 to determine which drive is causing damage.
The drive heads are visi ble through the media slot. Replace any drive mechanism which is determined to
be damaging the media. -
• If the fan is not operating check that the HP 9122 is receiving primary power that the voltage select
switch is set correctly, and that the primary fuse is good. Also check that the fan is plugged into the con-
troller peA correctly, and that the power supply voltages on the controller PCA are correct.
(3
If possible, determine whether the customer has been using HP double-sided media. If the customer is
using media from other sources, or HP single-sided media in double-sided mode, it is possible that media
could be the caUSie of the problem.
Some media related problems which have occurred include visible wear of the disc, and a high pitched sound
from the drive while the disc is
'~eing
accessed. These problems have occurred when single-sided HP media
is being used heavily with the HP 9122 (instead of its intended use;to exchange data with single sided disc
drives) and with media from other vendors. Note that the head resonance problem may be found occasional-
ly as an independen.t failure mode also.
Additional media related problems may occur as failure to initialize media, and intermittent failures.. In
some cases, media may cause an accumulation of residue on the read/write head of the disc drive which
must be removed, if possible, before the drive will work properly with HP media. Heads may be cleaned
using the 09122-89415 cleaning disc and the HD_CLN routine in the 5S/80 Exerciser SERVC module to
exercise the disc drive during the cleaning.
Power-on self test
The power-on self test tests the RAM, ROM, FDC, HP-IB chips, and performs a seek test (checks the track 0
detector) on each drive if no
rnecj~ia
is installed in the 9122. In addition, if media is installed in the drives, a
motor speed test is perfonned (checks the time between index pulses). If the media is formatted in a double-
sided format and not write protected a write/read test is also performed on the system cylinder, which does
not affect any user data. (The write/read test is not performed
if
the disc is in singlesided format.)
Troubleshooting Procedures
• All tests specified in the following procedures should be performed using HP double-sided media ONLY .
• If an HP-85 and the SS/80 Exerciser, PIN 5010-0310, are available it is recommended that the Exerciser
be used to diagnose the failure and verify a repair. See information on use of the SS/80 Exerciser on page
4-11.
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