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DISASSEMBLY PROCEDURES
Console Procedures 2.4 Remove the ATAPI shield over the back
of the DVD drive. If your unit has the folded
CAUTION: The DVD drive mechanism should foil type, peel the foil back from the rear of
not be closed by pushing it shut with no power the DVD mechanism until you can access
applied to the console. Doing so could damage the cables. If you have the formed metal
the drive. It must be closed with power applied shield, lift up the rear of the DVD mechanism
so that the locking mechanism inside the drive and slide the shield off. Unplug the ATAPI
will engage properly when the drawer is and power cables from the rear of the DVD
closed. mechanism.

Note: Refer to Figure 4 for the following 2.5 If you could not apply power to the
procedures. console to remove the drawer bezel in step
2.3, lift up on the back of the DVD drive until
1. Top Cover Removal the DVD drawer bezel (27) pops off the front
of the DVD drive drawer. You need to lift the
1.1 Place the console on the bench with the drive up quite a bit to get this to work. Once
front facing toward you. On the rear of the the drawer extension is off, slide the DVD
console and using finger pressure only, drive to the rear until it is out from under the
press inward in the center of the rear panel edge of the bezel.
just below the edge of the top cover (2).
When you have pressed the rear panel in Re-assembly note: Be sure to install the
approximately 1/4", lift upward on the top two Phillips-head screws (6) that were
cover and release the pressure on the rear removed in step 3.5. These screws are used
panel of the console. The finger in the center to align the drive with the console casting
of the top cover should be sitting on top of (14).
the corresponding latch hole in the rear
panel. Once the center finger has cleared, lift 3. Main PCB Removal
upward on the rear edge of the top cover
until the four tabs to the sides clear the 3.1 Perform procedure 2.
console rear panel.
3.2 Unplug the ribbon cable at J6500 on the
1.2 Slide the top cover to the rear of the main PCB (20). This cable runs to the dis-
console approximately 1/2". Lift off the top play PCB (25). Carefully lift off the adhesive
cover. foil strip from the casting. This strip runs
under the ribbon cable from the casting to
2. DVD Drive Removal the display PCB. You will need to re-use this
strip later.
2.1 Perform procedure 1.
3.3 Using a size T-15 Torx head driver,
2.2 Using two large flat-tip screwdrivers, remove the nine screws (13) that secure the
press down and pry the tabs on one side of casting (14) and main PCB (20) to the
the spring clamp (3) away from the casting console base (21).
(14) at the corners. Lift the spring clamp off
of the DVD drive. 3.4 Remove the clip (12) that secures the
amplifier output IC to the heatsink (9). Care-
2.3 Apply power to the console and press fully pry the output IC slightly away from the
the STOP/EJECT button to open the DVD heatsink. Lift the casting and heatsink as-
drawer. Once the drawer is open, remove sembly out of the chassis. Be sure to retain
the DVD drawer bezel (27). Press the STOP the two thermal pads under the casting.
/EJECT button again to retract the drawer.
Remove power from the console.
38
DISASSEMBLY PROCEDURES
3.5 On the rear of the console base (21), Release the four tabs on the bottom of the
unclip the four tabs that secure the I/O panel base directly behind the bezel sub assembly.
(19) to the base. Pull away and down on the Take care not to drop the LCD display PCB.
top of the I/O panel until it unclips from the
base. It should come off completely. 4.4 Place the bezel sub assembly face
down on a soft surface. Lift the LCD display
3.6 Carefully lift the front edge of the main PCB out of the bezel sub assembly. Using
PCB (20) out of the base. Slide the main a small flat-tip screwdriver, flip up the edge
PCB forward slightly until it clears the jacks of the ZIF connector at J2. Unplug the ribbon
on the back of the board. Lift the main PCB cable. Take care to not plug and unplug this
out of the base. cable too many times. It has a carbon coat-
ing that wears off after just a few removals
Re-assembly notes: and insertions, ruining the cable.
Be sure to install a thermal barrier, Bose
part number 267574-001 into the console Bass Module Procedures
chassis before re-installing the main PCB.
On the main PCB, check to make sure that Refer to Figure 2 for the following proce-
the large thermal pad (16) is in place on top dures.
of the DVD decoder IC (U3000) and the
small thermal pad (17) is in place on top of 1. Rear Enclosure Removal
the CODEC IC (U4000). Check that the
eight small EMI shield conductive strips 1.1 Place the bass module on its side.
(15,18) are in place in the groove around the Using a Phillips-head screwdriver, remove
bottom of the casting (14). the four screws (9) that secure the rear
On the heatsink (9), use a straight-edge enclosure (8) to the bass module.
razor blade to scrape off any thermal phase
change pad (11) material. Take care to not 1.2 Slide the rear enclosure off of the bass
scratch the coating on the heatsink. Clean off module.
any residue with alcohol. On the main PCB,
clean any thermal phase change pad residue 2. Power Transformer Removal
off of the output IC. Apply a small amount of
thermal compound to the back of the output 2.1 Perform procedure 1.
IC.
2.2 On the bass module PCB/heatsink
4. LCD Display PCB Removal assembly, unplug the cables at J3 and J5
that run to the power transformer. Unplug
4.1 Perform procedure 2. the woofer harness cable at J7.

4.2 On the main PCB (20), unplug the ribbon 2.3 Using an 8/32" nut driver, remove the
cable at jack J6500. Peel off the foil ground four nuts (6) that secure the power trans-
strap (24) located directly under the ribbon former (7) to the bass module enclosure.
cable. You will need to re-install this later.
2.4 Lift the power transformer off of the
4.3 Using a small flat-tip screwdriver, press mounting studs (5) and out of the enclosure.
in the tabs that secure the bezel sub assem-
bly (26) to the console base (21). There are
two located at the top of the base behind the
front panel near the ribbon cable and the
heatsink (9). There are two more inside the
opening for the DVD drawer.

39
DISASSEMBLY PROCEDURES
3. Bass Module PCB/Heatsink Assembly 321 GS Satellite Array Procedures
Removal
Note: Refer to the figure below for the
3.1 Perform procedure 1. following procedures.

3.2 On the bass module PCB/heatsink 1. Grille Removal
assembly (10), unplug the cables at J3 and
J5. Unplug the woofer harness cable at J7. 1.1 Using a scribe or small flat blade screw-
driver to grasp the edge of the grille (2).
3.3 Remove the four screws (11) that secure Gently pull the grille away from the enclo-
the bass module PCB/heatsink assembly to sure.
the enclosure. Lift it out of the enclosure.
2. TwiddlerTM Removal
321 Satellite Array Procedures
2.1 Perform procedure 1.
Note: The standard 321 (non-GS) satellite
arrays are non-repairable. The only parts that 2.2 Using a Philips-head screwdriver, re-
can be replaced are the grille and the name- move the four screws (5) that secure the
plate. driver (1) you wish to remove.

1. Grille Removal 2.3 Lift the driver out of the enclosure and
remove the two faston connectors of the
1.1 Wrap some masking tape around the wiring harness.
shaft of a flat-tip screwdriver approximately
1/2" back from the end. This is needed to Re-assembly note: Be sure that the driver
protect the plastic enclosure of the array. gasket is properly aligned behind the driver
to ensure an airtight seal.
1.2 Place the satellite array on its back on a
bench. Use your thumb to press down on the
array grille at the center of the curve near the 1
side. At the same time, use the screwdriver
to pry the end of the grille off of the array
enclosure. Repeat this at the other end of the
grille. 2




2. Nameplate Removal 3
1
4 4x
5 8x
2.1 Perform satellite array procedure 1.

2.2 On the back of the grille (1), unbend the
two metal legs that secure the nameplate (2)
to the grille. Pull the nameplate away from
the grille.




40
TEST PROCEDURES
321 Required Test Equipment and Cables
1. Audio Signal Generator.
2. Analog to S/PDIF converter
3. S/PDIF to optical converter
4. Abex test DVD (TDV-540A)
5. Video monitor
6. Composite Video cable
7. S-Video cable
8. Optical cable
9. Oscilloscope
10. Volt Meter
11. AM/FM Signal Generator.
12. Model 321 remote control part number 259820-001.
13. Model 321 TAP cable, p/n 266603
14. B+B Electronics RS-232 to TTL level shifter, model 232LPTTL (available on-line at: http://
www.bb-elec.com).
15. IBM Compatible PC
16. Test CDs as listed below or equivalent.

Parameter Nominal Limit Suggested Test disc
Defect Tracking (void) 1.0 mm 0.8 mm Pierre Vernay, test CD#2
Defect Tracking (black dot) 1.0 mm 0.8 mm ABEX test disc TCD-725R
Defect Tracking (scratch) 1.6 mm 1.0 mm ABEX test disc TCD-721 R
Defect Tracking 75 mm 65 mm ABEX test disc TCD-725R
(finger print)
Defect Tracking 1.0 mm 0.7 mm ABEX test disc TCD-732RA
(warped disc)
Defect Tracking 210 mm 140 mm ABEX test disc TCD-714R
(eccentric disc)




41
TEST PROCEDURES
1. Initial Product Test

Note: Before taking the unit apart or performing any repair process, an attempt to verify the cus-
tomer complaint must be made.

1.1 Read any customer note included with the unit.

2. Verify Customer Complaint

2.1 Attempt to verify the complaint before opening the unit or performing any repairs. Cus-
tomer complaint not verified, discuss with customer.

2.2 Customer complaint verified, troubleshoot and repair the unit.

3. Check the software revision of the unit. Refer to the Bose