Maintenance Pressure leak error

Error code
  • 034879 Maintenance Pressure leak error
Occurrence condition
  • The negative pressure failed to drop below the specified value in a pre-CL leak check.
Assumed cause
  • Head cap touch failure
  • Foreign substances in the space between the cap and head
  • Deformed or missing cap lip
  • Cap atmospheric relief valve leak
  • Waste ink flow path leak
  • Selector Unit failure
  • Flow path valve leak
Related parts
  • Cap Unit
  • Waste ink tube unit
  • Ink System Unit
Troubleshooting

Step

Confirmation and action

YES

NO

1

Check the connection in the Cap Unit two-port joint

  • Did the trouble go away?
End Go to step 2
2

Check the joint connection between the Ink System Unit and main unit

  • Did the trouble go away?
End Go to step 3
3

Check harness connection

Are the harness connectors that connect to the Ink System Unit properly connected?

If not, reconnect them properly.

[Part(s) to be checked]

  • Ink System Unit Connector
  • Other connectors and FFCs you disconnected and reconnected

[Action]

  • Connect the connectors properly.

Is the error resolved?

End

Go to step 4

4

Replace the Cap Unit

  • Did the trouble go away?
End Go to step 5
5

Replace the Cap Motion Unit

  • Did the trouble go away?
End Go to step 6
6

Replace the Ink System Unit

  • Did the trouble go away?
End Go to step 7
7

Replace the waste ink tube unit

  • Did the trouble go away?
End Go to step 8
8

Replace the Main Board

  • Did the trouble go away?
End Go to step 9
9

Replace the MCU board

  • Did the trouble go away?
End

Contact EPSON Local Service Representatives