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the circuit board.
3.
Observing diode polarity, wrap each lead of the
new diode around the corresponding lead on the circuit
board.
4.
Securely crimp each connection and solder it.
5.
Inspect (on the circuit board copper side) the solder
joints of the two "original" leads. If they are not shiny,
reheat them and if necessary, apply additional solder.
Fuse and Conventional Resistor
Removal/Replacement
1.
Clip each fuse or resistor lead at top of the circuit
board hollow stake.
2.
Securely
crimp
component around notch at stake top.
3.
Solder the connections.
CAUTION: Maintain original spacing between the
replaced component and adjacent components and the
circuit
board
to
prevent
temperatures.
Circuit Board Foil Repair
Excessive heat applied to the copper foil of any printed
circuit board will weaken the adhesive that bonds the
foil to the circuit board causing the foil to separate from
or "lift-off" the board. The following guidelines and
procedures should be followed when- ever this
condition is encountered.
At IC Connections
To repair a defective copper pattern at IC connections
use the following procedure to install a jumper wire on
the copper pattern side of the circuit board. (Use this
technique only on IC connections).
1.
Carefully remove the damaged copper pattern with
a sharp knife. (Remove only as much copper as
absolutely necessary).
2.
carefully scratch away the solder resist and acrylic
coating (if used) from the end of the remaining copper
pattern.
3.
Bend a small "U" in one end of a small gauge
jumper wire and carefully crimp it around the IC pin.
Solder the IC connection.
4.
Route the jumper wire along the path of the
out-away copper pattern and let it overlap the previously
scraped end of the good copper pattern. Solder the
overlapped area and clip off any excess jumper wire.
the
leads
of
replacement
excessive
component
At Other Connections
Use the following technique to repair the defective
copper pattern at connections other than IC Pins. This
technique involves the installation of a jumper wire on
the component side of the circuit board.
1.
Remove the defective copper pattern with a sharp
knife. Remove at least 1/4 inch of copper, to ensure that
a hazardous condition will not exist if the jumper wire
opens.
2.
Trace along the copper pattern from both sides of
the pattern break and locate the nearest component
that is directly connected to the affected copper pattern.
3.
Connect insulated 20-gauge jumper wire from the
lead of the nearest component on one side of the
pattern break to the lead of the nearest component on
the other side.
Carefully crimp and solder the connections.
CAUTION: Be sure the insulated jumper wire is dressed
so the it does not touch components or sharp edges.
6
Copyright ⓒ 2017 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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