HP Deskjet 720C banner light

I get the following error message Printer Mismatch the banner lever
does not match software. The printer stops printing, banner light
stays on. Disabling the printer's bi-directional communication allows
it to print. I have two of these printers and both exhibit the same
error. I assume the switch or the activating mechanism is at fault. I
realize these are an old but would rather fix if I can, as they serve
my purpose. I know how to disassembled it but lack the expertise on
servicing printers. I assume schematics are unavailable? Any
information would be appreciated.TIA

"Don Whynot" wrote in message
...
I get the following error message Printer Mismatch the banner lever
does not match software. The printer stops printing, banner light
stays on. Disabling the printer's bi-directional communication allows
it to print. I have two of these printers and both exhibit the same
error. I assume the switch or the activating mechanism is at fault. I
realize these are an old but would rather fix if I can, as they serve
my purpose. I know how to disassembled it but lack the expertise on
servicing printers. I assume schematics are unavailable? Any
information would be appreciated.TIA

My recollection is that corrosion occurred on the connection of the
switch or its pcb, causing it to always appear in the "banner" (shorted)
position. If you do not use banner printing you could just remove the
traces to the switch, otherwise trace out the traces to the switch and
clean both ends of the connector.

I have never seen a schematic for the DJ 720.

Regards,
Bob Headrick, MS MVP Printing/Imaging

"Bob Headrick" wrote in message
...

"Don Whynot" wrote in message
...
I get the following error message Printer Mismatch the banner lever
does not match software. The printer stops printing, banner light
stays on. Disabling the printer's bi-directional communication allows
it to print. I have two of these printers and both exhibit the same
error. I assume the switch or the activating mechanism is at fault. I
realize these are an old but would rather fix if I can, as they serve
my purpose. I know how to disassembled it but lack the expertise on
servicing printers. I assume schematics are unavailable? Any
information would be appreciated.TIA

My recollection is that corrosion occurred on the connection of the
switch or its pcb, causing it to always appear in the "banner" (shorted)
position. If you do not use banner printing you could just remove the
traces to the switch, otherwise trace out the traces to the switch and
clean both ends of the connector.

I have never seen a schematic for the DJ 720.

Regards,
Bob Headrick, MS MVP Printing/Imaging

In my case disabling the printer's bi-directional communication was only a
temporary fix. I never use banner printing but the printer configuration was
randomly reset back to default, probably due to one of my virus or registry
cleaners. (?) Never failed, when I tried to print something I got the error
message. I appreciate your help with a permanent fix, thank you.