Midway 16-20044-101, 16-20040-101 manual Audio Troubleshooting Table

Audio Troubleshooting Table

	SYMPTOM	CAUSE	REQUIRED ACTION
			Enter Menu System by pressing and holding
•	No audio	Improper volume	TEST MODE switch. From Operator (Main)
		setting	Menu, choose VOLUME MENU. Check that
•	Video is present		Attract Music is on (enabled). Verify that all
			volume levels are set well above zero. If
• VGM (video game machine)			necessary, change levels to make VGM audible.
	appears to operate normally		Turn off VGM power. Assure that wiring harness
		Faulty wiring	connectors attach and fully seat onto mating
			board connectors. Verify that harness connects
			to computer. Check audio cable connectors in
			same way.
		Faulty or obstructed	Remove grilles and inspect speakers. Free
		speaker	speaker cones, terminals, mounting screws and
			magnets of loose parts or wires.
		Faulty Audio Board	Verify proper operation of Audio Board by
			placing it in working VGM.
			1. Check that cabinet wiring is correct for this VGM.
• Constant low hum from all		Faulty wiring	2. Verify that cabinet wiring provides separate
	speakers.		wires (not common return) for each speaker.
			3. Check connection of all cabinet ground wires.
			1. Run power-up self-test sequence. Note errors
		Faulty Audio Board	that VGM finds during tests. Compare Diego
			Board LEDs with LED indicator status charts.
			Note discrepancies.
			2. Verify that Audio Board operates by placing it in
			working VGM. Replace bad parts.
			Using 2 Volt AC setting on digital voltmeter,
		Faulty power supply	measure voltages at speaker terminals. Any
			reading indicates unstable supply that may
			contain ripple or noise.
			1. Turn off VGM power. Remove grilles and check
• Audio is distorted, muffled or		Faulty or improper	speakers. Assure that speakers are full range
	has missing frequencies.	speaker	(100 to 10,000 Hz response) and rated for at
			least 20 watts. Woofers must be rated for at
			least 40 watts.
			2. Verify proper speaker operation by connecting
			speaker in question to working VGM.
			Multiple-speaker installations: Check for
		Faulty wiring	reversed wires at one speaker. Weak low
			frequencies and thin or hollow sound quality is
			symptom of incorrectly phased speakers. Sound
			tests may not detect this condition, but you can
			hear it during VGM operation.
			1. From Diagnostics Menu, choose SOUND TEST.
•	Dead sound channel	Faulty speaker	Recheck speakers with audio signals provided
			by test.
			2. Verify proper speaker operation by connecting
			speaker in question to working VGM.
			Run power-up self-test sequence. Note errors
		Faulty circuit board	that VGM finds during tests. Compare circuit
			board LEDs with LED indicator status charts.
			Note discrepancies.
			Verify that cabinet wiring is correct. Assure that
		Faulty wiring	all speakers connect to audio wires. Audio cable
			must be fully seated in Computer Line Output
			Jack. Check for broken or shorted wires.

Troubleshooting 6-6