York YJHMXH007BARR-FX Service Manual page 23

Functions and control
First, connect the test program terminal on the mainboard. Then connect the system to the power
circuit. The test program will operate as follows.
HV series display: The buzzer rings for one time—the signal will be sent to outdoor system for 0.5
second— the violet is sent for 0.5-- the background light turns to white—the back ground light turns to
white—the background light turns to white—the background light is fully lighted for 0.5 second—LED
screen lights for 0.5 second— the step-in motor fully output for 0.5 second—then the motor doesn't
output for 0.5 second—the motor fully output again for 0.5 second. The test program finishes.
5.1.20 Time cutting function:
Connect the test program terminal on the mainboard after connecting the system to the power circuit.
The CPU of the main control will be 60 times faster.
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Domestic Air Conditioner