Lexmark C782 Service Manual - Page 117

5061 DC power service check The machine is partially operative, a motor turns, display is on, or the Power On LED may be on or off. Step 1 Actions and questions Does the printer beep 5 times and the operator panel display all diamonds? 2 DC power to system board-Turn the power off, and disconnect the LVPS cable to J18 on the system board. Turn the power on, and check the following voltages on the LVPS cable: J18-1 J18-2 +3.3 V dc +3.3 V dc J18-3 J18-4 +5 V dc +5 V dc J18-5 +24 V dc J18-6 J18-7 J18-8 +24 V dc +24 V dc +3.3V dc J18-9 J18-10 Ground Ground J18-11 Ground J18-12 J18-13 J18-14 Ground Ground Ground J18-15 J18-16 Ground Ground Note: All voltages are approximate values. Are the voltages correct? 3 Unplug all cables from the system board, except JOPP1, J18, and J20. See "System board" on page 5-7. Does the printer power up and display a message? 4 Turn off the printer, and plug in the cable for the component that is related to the error presented. For example, for the 109.xx Service Printhead error, plug in the black printhead JMMK1 and JMK1. Use connector locations on "System board" on page 5-7. Repeat this step until the original DC power problem occurs. Does the DC power problem occur? Yes Go to "Operator panel LCD/ status LED/ buttons service check" on page 2-88. Go to step 3 Go to step 4 Check the cable and component that was last connected to system board for short. No Go to step 2 Replace the LVPS assembly. See "LVPS assembly removal" on page 4-53. Replace the system board. See "System board removal" on page 4-89. If printer comes to Ready, connect the remaining cables and print. Diagnostic information 2-75