E020-0X90 Upon Installation Due To The Return Failure Of A Contact Spring On The Developing Bias - Canon imageRUNNER ADVANCE C2000 Series Technical Workbook

Service work
Release the stuck coupling. Make sure to check that the error does not recur after inserting the drum unit
into the main unit. If it recurs, there may be other factors to cause the error.
[Caution] If the drum unit coupling hits against something, it may get stuck with the guide rail. Handle the
drum unit coupling with care.
Title

E020-0x90 upon installation due to the return failure of a contact spring on the Developing bias

Symptom
E020-0x90 occurred upon installation.
- E020-0x90: ATR Sensor error or toner supply error (x=0:Y, 1:M, 2:C, 3:Bk)
Cause
The leading edge of a contact spring on the Developing bias consists of a double ring. The return failure of a
spring occurred due to this ring being crossed resulting in a contact failure and a subsequent error.
Service work
1) Detach the cap by removing the claw of the contact spring cap [A].
pg. 69