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KLV-26/32/37U300A

The circuit boards used in these models have been processed using
Lead Free Solder.
The servicing of these boards requires special precautions to be taken
as outlined below.

It is strongly recommended to use Lead Free Solder material in order to guarantee optimal quality of new solder joints.
Lead Free Solder is available under the following part numbers:

Due to the higher melting point of Lead Free Solder the soldering iron tip temperature needs to be set to 370 degrees centigrade.
This requires soldering equipment capable of accurate temperature control coupled with a good heat recovery characteristics.

For more information on the use of Lead Free Solder, please refer to http://www.sony-training.com     

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KLV-26/32/37U300A

SAFETY CHECK-OUT

After correcting the original service problem, perform the
following safety checks before releasing the set to the customer:

1. Check the area of your repair for unsoldered or poorly sol-

dered connections. Check the entire board surface for solder
splashes and bridges.

2. Check the interboard wiring to ensure that no wires are

“pinched” or touching high-wattage resistors.

3. Check that all control knobs, shields, covers, ground straps,

and mounting hardware have been replaced. Be absolutely cer-
tain that you have replaced all the insulators.

4. Look for unauthorized replacement parts, particularly transis-

tors, that were installed during a previous repair. Point them
out to the customer and recommend their replacement.

5. Look for parts which, though functioning, show obvious signs

of deterioration. Point them out to the customer and recom-
mend their replacement.

6. Check the line cords for cracks and abrasion. Recommend the

replacement of any such line cord to the customer.

7. Check the antenna terminals, metal trim, “metallized” knobs,

screws, and all other exposed metal parts for AC leakage. Check
leakage as described below.

LeakageTest

The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microamperes).
Leakage current can be measured by any one of three methods.

1. A commercial leakage tester, such as the Simpson 229 or RCA

WT-540A. Follow the manufacturers’ instructions to use these
instructions.

2. A battery-operated AC milliampmeter. The Data Precision 245

digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a

VOM or battery-operated AC voltmeter. The “limit” indica-
tion is 0.75V, so analog meters must have an accurate low volt-
age scale.
The Simpson’s 250 and Sanwa SH-63TRD are examples of
passive VOMs that are suitable. Nearly all battery-operated
digital multimeters that have a 2 VAC range are suitable (see
Figure A).

How to Find a Good Earth Ground

A cold-water pipe is a guaranteed earth ground; the cover-plate
retaining screw on most AC outlet boxes is also at earth ground. If
the retaining screw is to be used as your earth ground, verify that
it is at ground by measuring the resistance between it and a cold-
water pipe with an ohmmeter. The reading should be zero ohms.

If a cold-water pipe is not accessible, connect a 60- to 100-watt
trouble- light (not a neon lamp) between the hot side of the
receptacle and the retaining screw. Try both slots, if necessary, to
locate the hot side on the line; the lamp should light at normal
brilliance if the screw is at ground potential (see Figure B).

To Exposed Metal
Parts on Set

0.15 

µ

F

Earth Ground

AC
Voltmeter
(0.75V)

Figure A. Usingan AC voltmeter to check AC leakage.

Figure B. Checking for earth ground.

KLV-26/32/37U300A

10

SECTION 1 : DISASSEMBLY

Gently place the TV set
face down on the table.

KLV-26U300A:
Remove 3 screws to
release the Tabletop
Stand from the unit.

KLV-32U300A:
Remove 3 screws to
release the Tabletop
Stand from the unit.

KLV-37U300A:
Remove 4 screws to
release the Tabletop
Stand from the unit.

Service Position

Stand Removal

KLV-26/32/37U300A

11

Rear Cover
Removal

Wall Mount
Bracket
Removal

KLV-26U300A:
Remove 16 screws to
release the rear cover.

KLV-32U300A:
Remove 16 screws to
release the rear cover.

KLV-37U300A:
Remove 16 screws to
release the rear cover.

Remove 6 screws to
release the Wall Mount
Bracket.