Service manual

remove the sense cable (gray ribbon cable) and the transformer primary
connector (7 wire green connector) from the AC Mains board.
10. While firmly holding the AC Mains board, remove the three (3) screws on the
top of the chassis and remove the board.
11. If the unit was subjected to overvoltage conditions (> 270 VAC), the AC
Mains board fuse could be damaged. Locate the fuse (F1) on the AC Mains
board (between Relay 1 and the AC input connector) and check the continuity
with an ohmmeter. If the fuse is open, the AC Mains board will have to be
replaced.
Refer to Meyer Sound Self Powered Series MP-2/4 AC Mains Service Procedure
(# 17.033.022.01). for replacement procedures for the AC mains module or
contact the Meyer Sound Service Department for links to service videos for this
product or further assistance.
12. If the AC Mains appears to be fine, try replacing the board with a known good
working module (either a new one or from another unit). Install the good board
and repeat the power up sequence described in step 7.
13. If the unit still does not power up properly, it is likely that the transformer or
the power supply module is damaged.
You can refer to Meyer Sound Self Powered Series MP-2/4 Power Supply
Service Procedure (#17.033.076.01) for replacement procedures for the Power
Supply board or contact the Meyer Sound Service Department for links to service
videos for this product or further assistance.
D. Unit powers up and immediately shuts off:
This condition is typically an indication of partial MOSFET failure.
Generally, when one side of a two channel amplifier has shorted MOSFETs, a
large DC offset is created on that side from the voltage supply rails.
The amplifier sensing circuits detect this condition on power up and send a fault
signal, and the amplifier shuts off.
Please refer to Section A for troubleshooting information.
Note 1: If the unit is excessively hot (i.e. the heatsink > 80
°C), it will shut off. Let
the unit cool sufficiently and try again.
E. Unit powers up but does NOT pass signal:
1. If the amplifier is in the speaker cabinet, remove the eight (8) large head
screws that attach the amplifier to the cabinet. As you slowly remove the
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