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Power Supply Test
To test power supplies that are already installed in the machine, use the following procedures:
1. Check the 5V LED at location D43 and the 15VLED at location D32 on the main PCB. Both of
them should always be illuminated when the machine is turned on.
2. Check the status of LEDs at locations D52, D53, and D45. They should be blinking.
3. If any of the LEDs are not correct (on or blinking as appropriate) as described in steps 1 and 2
above, turn the machine OFF, remove the lower arm rear cover, disconnect the 36V power harness
from the main PCB.
4. Use a voltage meter set to measure DC voltage and measure the voltage output on the 36V pow-
er harness. Place the ground lead from the voltage meter on the pin to any of the black wires and
the positive (hot) lead from the voltage meters on any one of the red wires. Turn the machine ON
and check the voltage which should be between 34.5V to 38V DC.
5. If the voltage input measured from any of the red wires in the 36V power harness is not between
34.5V to 38V DC, wriggle the cable and look for voltage change.
Figure 1 - Power Supply Voltage Measurement Points (wires disconnected for illustration only)
6. If the voltage changes, measure 36V DC output at the power supply terminal block. If the power
output is stable and measures between 34.5V to 38V DC, then the 36V power harness is proba-
bly bad. Replace the harness and if it does not solve the problem, proceed with testing the power
supply unit. Otherwise, reinstall the covers and tighten the screws to the Torque Specifications.
Check the power supply unit itself:
7. Turn the machine off.
8. Disconnect the A/C wallpower supply harness from the main power input connector. Disconnect
the external Ethernet cable.
9. Remove the power supply assembly from the machine following the procedures for removing the
power supply in the section titled “Power Supply Assembly”.
10. Set the power supply on a table or work bench with an A/C outlet close by.
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