GE MAC 600 SPY, Service Manual

Page: 28 / 127

3-4 MAC
TM
600 Revision G
2047426-002
Troubleshooting: General Fault Isolation
Visual Inspection
A visual inspection of the equipment can detect disconnected cables,
debris on circuit boards, missing hardware, and loose components. These
could cause symptoms, and equipment failures.
NOTE
Perform the visual checks before starting any troubleshooting
procedures.
Table 3-1. Visual Inspection List
Sl No: Area Look for:
1 I/O connectors and
cables and AC power
cord

Fraying or other damage

Bent prongs or pins

Cracked housing

Loose screws in plugs
2 Interface cables

Excessive tension or wear

Loose connection

Strain reliefs out of place
3 Circuit boards

Moisture, dust, or debris (top and bottom)

Loose or missing components

Burn damage or smell of over-heated
components

Socketed components not firmly seated

PCB not seated properly in edge connectors

Solder problems: cracks, splashes on board,
incomplete feed through, prior modifications or
repairs
4 Ground wires/wiring

Loose wires or ground strap connections

Faulty wiring

Wires pinched or in vulnerable position
5 Fasteners Loose or missing screws or other hardware,
especially fasteners used as connections to ground
planes on PCBs
6 Power source

Faulty wiring, especially AC outlet

Circuit not dedicated to system
(Power source problems can cause static
discharge, resetting problems, and noise.)
7 Keypad

Cuts or cracks in keypad membrane

Illegible labels
8 LCD display Scratched or opaque display filter
9 Battery pack

Cracked, swollen, or leaky battery pack
enclosure

Debris on battery pack electrical contacts