C8402 (bizhub C759/C659)

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Contents

Trouble type	C8402: Multi feed detection board failure (When UK-501 is installed)
Rank	C
Trouble detection condition	-The AD value went below the predetermined the HI side threshold for two consecutive times. -The AD value went above the predetermined the LOW side threshold for two consecutive times.
Trouble isolation	DF
Relevant electrical parts	-Multi feed detection board/1 (transmitter) (MFDB/1) -Multi feed detection board/2 (receiver) (MFDB/2) -Sensor control board (SCB) -DF control board (DFCB)

 Procedure

1. Remove the film stuck on the window of the lower guide assembly.
2. Use the adjustment sheet for double feed detection kit (UK-501), and select [Service Mode] -> [ADF] -> [Multi-Feed DetectionAdj.].
3. Use the misdetected paper, and select [Service Mode] -> [ADF] -> [Multi-Feed DetectionAdj.].
4. Check the connector between MFDB/1-relay CN114-SCB CN104 for proper connection and correct as necessary.
5. Check the connector between MFDB/2-SCB CN103 for proper connection and correct as necessary.
6. Check the connector between SCB CN101-DFCB CN8 for proper connection and correct as necessary.
7. MFDB/1 load check
   • Check code: 60
   • Multi code: 161
   • Control signal: SCB CN104
   • Location of electrical component: DF 11-L
8. MFDB/2 load check
   • Check code: 60
   • Multi code: 161
   • Control signal: SCB CN103
   • Location of electrical component: DF 10-J
9. Replace SCB. (Part# A796H01A00)
10. DFCB ICP11 conduction check.
11. Replace DFCB. (Part# A782H0010A)

L.3.14.7 (Link to the Field Service Manual)