Daikin ComfortNet DX7TC Service Instructions Manual page 75

SERVICING
Emerson UltraCheck-EZ™ Diagnostic Tool
The Emerson UltraCheck-EZ™ diagnostic tool may be used to
diagnose the ECM motor.
HIGH VOLTAGE
Disconnect ALL power before servicing or installing
this unit. Multiple power sources may be present.
Failure to do so may cause property damage, personal
injury or death.
To use the diagnostic tool, perform the following steps:
1. Disconnect power to the air handler.
2. Disconnect the 4-circuit control harness from the motor.
3. Plug the 4-circuit connector from the diagnostic tool into
the motor control connector.
4. Connect one alligator clip from the diagnostic tool to a
ground source.
5. Connect the other alligator clip to a 24VAC source.
NOTE: The alligator clips are NOT polarized.
NOTE: The UltraCheck-EZ™ diagnostic tool is equipped with a
nonreplaceable fuse. Connecting the tool to a source other than
24VAC could damage the tool and cause the fuse to open. Doing
so will render the diagnostic tool inoperable.
6. Turn on power to air handler or modular blower.
Line Voltage now present.
7. Depress the orange power button on the diagnostic tool
to send a run signal to the motor. Allow up to 5 seconds
for the motor to start.
NOTE: If the orange power button does not illuminate when
depressed, the tool either has an open fuse or is not properly
connected to a 24VAC source.
8. The green LED on the diagnostic tool will blink indicating
communications between the tool and motor. See table
below for indications of tool indicators and motor actions.
Replace or repair as needed.
WARNING
WARNING
Power Green
Button LED
OFF OFF
Rotating
ON Blinking Rotating
ON OFF Rotating
ON Blinking
Rotating
ON OFF
Rotating
9. Depress the orange power button to turn off motor.
10. Disconnect power. Disconnect diagnostic tool.
11. Reconnect the 4-wire harness from control board to
motor.
Electrical Checks - High Voltage Power Circuits
HIGH VOLTAGE
Disconnect ALL power before servicing or installing
this unit. Multiple power sources may be present.
Failure to do so may cause property damage, personal
injury or death.
1. Disconnect power to air handler or modular blower.
2. Disconnect the 5-circuit power connector to the ECM
motor.
3. Turn on power to air handler or modular.
Line Voltage now present.
4. Measure voltage between pins 4 and 5 on the 5-circuit
connector. Measured voltage should be the same as the
supply voltage to the air handler or modular.
Motor
Indication(s)
Action
Confirm 24VAC to
TM
UltraCheck-EZ
Not
If 24VAC is confirmed,
diagnostic tool is
inoperable.
Motor and control/end
bell are functioning
properly.
Replace motor
control/end bell.
Not Check motor (see
Motor Check s below).
Replace motor
Not control/end bell; verify
motor (see Motor
Check s below).
WARNING
WARNING
tool.
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