When Outputting 4-Color Halftone Images In Duplex Mode, Circular Spots Appear On 2Nd Side: Grounding Spring For Eliminating Charges From Secondary Transfer Roller Has Poor Contact; Uneven Density (Transfer Failure) Sometimes Occurs: One Side Of Itb Cover Is Not Closed Firmly - Canon Color iR C3480 Service Manual

Chapter 15
Field Remedy
1. Check to see if the grounding wire extends off the cable cover and is trapped by the cover.
2. If the wire is trapped by the cover, re-arrange it so that it will not be pinched.
3. If the symptom still occurs, replace the cable unit including the grounding wire (loop sensor cable) by a new one.
Cause
The grounding wire from the static eliminator extended off the cable cover found in the fixing assembly, causing wire-pinching. This caused transfer failure,
resulting in polka-dot voids.
Reference
This symptom depends heavily on the moisture content of paper. If paper is dry, the symptom is hard to occur.
FM2-9444 Loop Sensor Cable
15.3.1.4.2 When outputting 4-color halftone images in duplex mode, circular spots appear on 2nd side: Grounding spring for eliminating
charges from secondary transfer roller has poor contact
Color iR C3380G / Color iR C2880G / Color iR C3380i / Color iR C3380 / Color iR C2880i / Color iR C2880 / iR C3480 / iR C3480i / iR C3080i / iR C2550
[ Inspected by Canon Inc. ]
Description
Since the grounding spring used for eliminating charges from the secondary transfer roller had poor contact, circular spot-like soiling occurred in 4-color
halftone area on the 2nd side of output images in a duplex job.
Field Remedy
1. In service mode > COPIER > PG > TYPE, select '5' (full halftone) and then output test images.
2. If the symptom appears on the test images, using a digital multimeter, check if there is electrical continuity between the grounding spring and rear end plate.
3. If there is no electrical continuity, check to see if the grounding spring is deformed; if so, replace the spring with a new one.
FC6-9623 Grounding Spring

15.3.1.4.3 Uneven density (transfer failure) sometimes occurs: One side of ITB cover is not closed firmly

Color iR C3380G / Color iR C2880G / Color iR C3380i / Color iR C3380 / Color iR C2880i / Color iR C2880 / iR C3480 / iR C3480i / iR C3080 / iR C3080i / iR
C2550
[ Inspected by Canon Inc. ]
Description
Since uneven density (transfer failure) sometimes occurs when making dozens of copies, the ITB cover was closed again for solution.
15-10
F-15-11
F-15-12
0017-9808
0018-7046