Samsung DMR57 Training Manual page 58

Is the voltage between Pin 6 and 7 of connector CN7 on the main board
measure +5VDC and the voltage between Pin 6 and 12 measure +12VDC?
If not replace the Main board. If the voltage is present replace the Sub
board.
Troubleshooting the dishwasher follows the same logical troubleshooting
procedures as other appliances. Always start by checking the voltages that are
always on such as the 5 and 12 volt lines. These voltages are always there as long
as the power is applied to the machine. When measuring these voltages never
assume that the chassis is the reference ground. Use the ground connection from
the connector. Always consult the service manual for the model under repair for the
correct connections.
To check the individual motors and valves, the service mode can be used to
manually turn on these devices. This procedure is covered in a different module or
consult the service manual for the model under repair for the proper procedure.
No Power Troubleshooting
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