HP 8550 Service Manual - Page 525
No +24 UH printer
View all HP 8550 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 525 highlights
No +24 UH (printer) Cause Step Printer dc power 1 Connectors 2 Right cover 3 switch (main relay PCB) Delivery cover 4 and front cover switch (subrelay PCB) Printer power 5 supply Main relay PCB 6 Checks Yes/No Action Disconnect the power plug of the YES printer from copy module and connect it directly to the power outlet. Is the printer now receiving dc power? See "No dc power in the printer (+5V, +24 VB)" on page 522 Are connectors J641 through J643 NO and J6476 of the main relay PCB, connectors J671 and J673 on the sub-relay PCB, connector J102 of the power supply, and connector J227 on the dc controller PCB all connected securely? Connect the connectors securely Is there electrical continuity NO between connectors J641-1 (+24 VB) and J642-3 (PMP) on the main relay PCB when the right cover switch (SW641) is turned on? Replace the right cover switch on the sub-relay PCB. Is there electrical continuity NO between connectors J671-1 (PMP) and J671-2 (PFUFR) on the sub-relay PCB when the delivery cover/front cover switch (SW761) is turned on? Replace the delivery cover/front cover switch (SW761) on the sub-relay PCB. Disconnect the power plug of the NO printer from copy module and connect it directly to the power outlet. Turn on the printer power switch (see note on page 521) and measure the voltage between connectors J641 (+24 VB) on the main relay PCB and J641-4 (GND). Is it 24 V? Replace the printer power supply. Disconnect the power plug of the NO printer from the copy module, and YES then connect it directly to the power outlet. Turn on the printer power switch (see note on page 521) and measure the voltage between connectors J647B11 (+24 UH) on the main relay PCB and J647-A1 (GND). Is it 24 V? Replace the main relay PCB. Replace the dc controller PCB. EN Copy module troubleshooting 523