Disk Unit, Models 830/Sb2 And 840/Sb3 (Dedicated And Concurrent) - IBM iSeries 270 Service Manual

9074 Base I/O Tower" on page 260. Press the surfaces of the two latching mechanisms together
and tilt the top of the cover away from the frame to remove it.
g. Record the disk unit locations and then remove them from the disk unit enclosures that you just
uncovered.
Attention: The disk units are sensitive to electrostatic discharge (see "Work with electrostatic
discharge-sensitive parts" on page 585).
h. Remove the screws that hold the disk unit enclosures to the frame.
i. Remove the retaining screws that are located inside the disk unit enclosure.
j. Remove the disk unit enclosures.
k. Remove the screws that hold the center support bracket and shelf for the disk unit and removable
media enclosure to the frame.
l. Remove the support bracket and shelf.
m. Remove the base DASD board assembly (DB3).
8. Install the base DASD board assembly by reversing the removal procedure. After exchanging an item,
go to "Verify the repair" on page 558.
This ends the procedure.

Disk unit, Models 830/SB2 and 840/SB3 (dedicated and concurrent)

For use by authorized service providers.
Note: Determine if the system has logical partitions. Go to Determine if the system has logical partitions
before continuing with this procedure.
Attention: The disk unit is sensitive to electrostatic discharge (see Work with electrostatic
discharge-sensitive parts).
1. Were you directed here from Recovery procedures?
v Yes: Continue with the next step.
v No: Go to Recovery procedures. Then, return here.
2. After you have determined the location of the disk unit to replace, remove the covers for access. See
Models 830/SB2 with FC 9074 - Covers or Models 840/SB3 - Covers for the model that you are
working on.
3. Remove the EMC access plate that is over the location of the disk unit that you are removing. (For
location information, see Locations — Models 830, SB2 system unit with FC 9074 base I/O tower or
"Locations — Models 840, SB3 system unit with processor tower and FC 9079 Base I/O Tower" on
page 270 for the model that you are working on.) The associated tables will direct you to the remove
and replace procedures.
4. Are you removing or replacing a disk unit using concurrent maintenance?
v No: Perform Dedicated maintenance - Remove and replace (See page ) below.
v Yes: Perform Concurrent maintenance - Remove and replace (See page ) below.
Concurrent maintenance - Remove and replace
Attention: If removing the cover while powered on, errors may occur due to electromagnetic interference.
1. To remove a disk unit using concurrent maintenance perform the following:
a. Select System Service Tools (SST). If you cannot get to SST, select DST.
Do not perform a system IPL to get to DST.
b. Select Start a Service Tool —> Hardware Service Manager.
c. Select Device Concurrent Maintenance and enter the required information in the information
fields.
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Hardware (Remove and Replace; Part Locations and Listings)