Crown Audio 140MPA operation manual Troubleshooting, Vice Center for servicing

Commercial Audio Series Mixer-Amplifiers

4 Troubleshooting

CONDITION: No power to the mixer-amplifier.

POSSIBLE REASON:

• The mixer-amplifier’s Power switch is off.

• The mixer-amplifier is not plugged into the power receptacle.

• The mixer-amplifier’s high-voltage power sup- ply circuit breaker has tripped. Verify that the AC mains voltage is correct, then press the Reset button on the back panel.

CONDITION: Distorted sound.

POSSIBLE REASON:

• Input signal level is too high. Turn down your input volume controls. NOTE: Your mixer- amplifier should never be operated at a level which causes the Clip LEDS to illuminate con- stantly.

• Master volume level is too high. Turn it down to about 3/4 of maximum level.

	CONDITION: No sound.
	POSSIBLE REASON:
	• The amplifier is in “fault” mode. A Fault status
[NO GRAPHIC IS NEEDED	can be triggered when one of the amplifier’s
	protection circuits is activated. First disconnect
HERE]	your speakers from the affected channel(s) one
	by one to determine if one of the loads is
	shorted. If an amplifier channel has a thermal
	fault, there will be no indication on the front
	panel, but the amp will recover after cooling. If
	operation does not return to normal after
	restarting your amp, press the Reset button on
	the back of the unit. If that does not work, return
	the unit to Crown or an authorized Crown Ser-
	vice Center for servicing.

• No input signal.

• Input signal level is very low.

KEY

LED OFF

LED ON

page 14 Operation Manual