Midway Hydro Thunder, Operation Manual

Page: 91 / 105

Troubleshooting 6-4
VGM Startup Troubleshooting Table, continued
SYMPTOM CAUSE REQUIRED ACTION
Power problem
1. Inspect circuit boards under low-light conditions.
LEDs glow if processor circuits receive voltage.
Fan should be turning. These indications prove
presence of DC from power supply. Still,
voltages or signals may not be normal.
Computer has no internal LEDs.
2. Turn on VGM power. Using 20-volt DC setting on
digital voltmeter, measure DC voltages at power
connector pins. (Power supply voltage isn’t
adjustable.)
3. Using 2-volt AC setting on digital voltmeter,
measure same DC voltages as above. Any
reading here indicates that supply voltages are
unstable and may contain ripple or noise.
Faulty wiring
Turn off VGM power. Assure that wiring harness
connectors fully seat onto mating board
connectors. Verify that harness connects to
computer. Check other connectors in same way.
Improper jumper or
DIP switch settings Verify that circuit board jumpers are set as
intended. Check DIP switch settings.
•
VGM (video game machine)
appears non-functional.
•
Currency acceptor price
indicator is illuminated.
Faulty circuit boards
or arcade computer
1. Run power-up self-test sequence. Note errors or
failures during tests. Compare LEDs with LED
indicator status charts. Note discrepancies.
2. Turn off computer. Wait for hard disk to stop
spinning. Leave VGM power on. Loosen
computer case thumbscrews and lift off cover.
Turn computer power on. Listen for beeping
sounds. Compare beeps with Error Message
Troubleshooting Table.
CAUTION: Don’t remove or install any connector while power is turned on. Doing so
will damage circuit boards or hard disk drive, and void warranty.
Front View of Coin Door Interior View of Electronics