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The printhead fuse is blown
The printhead cable is damaged or incorrectly installed
Testing for a blown printhead fuse
Power the printer ON
Using a multimeter in DC Voltage mode, check the voltage in the power pins on the printhead connector:
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3. The expected voltage is 24V. If no voltage is detected, the printhead fuse is most likely blown.
Testing for a disconnected printhead cable
Power the printer OFF
Using a multimeter in Resistance mode, check the resistance in the data pins on the printhead connector:
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