Maytag Built-in Refrigeration, Руководство пользователя

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measurements should be equal regardless of which two terminals you are checking. There
are three identical windings attached to these terminals so the resistance of the windings
should be equal.
Because of the frequency of the following voltage tests, not all Multimeters may be
capable of measuring the correct voltage. These tests were made using a good quality
Multimeter. The same checks made with a more economical meter resulted in severely
lower voltage readings.
The voltages read by your meter will most likely not match the readings made with
another meter. The goal is to verify the presence of drive signals. The signal from the
Main Control board to the VCC board should read around 2.3VAC. This measurement
has been quite consistent with several different meters. The drive signal from the VCC
control board to the compressor is the one that will vary based upon the meter.
There are three outputs to the compressor. These are at CN05, pins 1,3 and 6. The voltage
read between any pair of these three wires should be the same. If you read 230VAC
between pins 1 and 3 you should also read 230VAC between pins 1 and 6 as well as
230VAC between pins 3 and 6. Likewise, if your meter registers 195VAC between pins 1
and 3 the readings between pins 1 and 6 and pins 3 and 6 should be 195VAC.
The easiest way to assure that the compressor is being driven at full speed is to activate
service test #16 in the service mode. To drive the compressor at the minimum speed,
activate service test #17. (see Service Test section) The system must be allowed 5
minutes of off time before activation of service test #16 or test #17. If five minutes have
not elapsed, the compressor PCB will not allow drive output to the compressor until the
five minutes have elapsed. Service Tests #16 and #17 will automatically cancel after
three minutes.
If the compressor is not operating the first check should be confirmation of a drive signal
from the Main Control Board to the Compressor PCB. A check of the AC voltage
between pins 1 and 2 of JP10 will give a reading of approximately 2.3VAC. If the
2.3VAC drive signal is present, the Main Control Board is sending the proper drive
signal.
The next step is to verify that the line voltage is available to the Compressor PCB at
CN01 between pins 2 and 5. If the AC voltage is available, check for output to the
compressor. Referencing CN05, pin 1, an AC voltage check to pin 6 will read
approximately 230VAC with the compressor running at full speed. While running at the
lowest speed, the measured output voltage may only be 130VAC. If the output voltage is
present when checking between pins 1 and 6 on CN05, move the probes to check
between pins 1 and 3 of CN05 and finally between pins 3 and 6 on CN05. The readings
in all of the three checks should be the same, if the voltage checks are equal and the
compressor is not operating, suspect a failed compressor. There is no way to operate this
compressor with a compressor start kit. The compressor must be driven by the solid-state
control board.