3-226 Phaser 7500 Printer Service Manual
Error Messages and Codes
RC Sample Block Fail-B-#1-Out
During the B (rough adjustment pattern) patch detection, the #1 (Yellow) patch at 
the MOB Sensor Out side did not satisfy the defined number of valid sample 
blocks.
Applicable Chain-Link Code
• 089-606: RC Sample Block Fail-B-#1-OUT
Initial Actions
• Power cycle the printer.
• If the problem persists, follow the procedure below.
When multiple failures with Chain No. 089 occur, take action according to the 
priority order.
Troubleshooting Reference
Applicable Parts Wiring and Plug/Jack Map References
■ Developer (Y), PL5.2.9
■ IBT Belt Unit, PL6.1.10
■ Imaging Unit (Y), PL8.1.4
■ MOB ADC Assy, PL18.1.4
■ MCU PWB, PL18.3.6
Troubleshooting Procedure
Step Actions and Questions Yes No
1 Check the density of Yellow color.
Is the density of Yellow color 
normal?
Go to step 2. Adjust to 
correct the 
density of 
Yellow color.
2 Check the connection between the 
MOB Sensor Out J151 and the 
MCU PWB J415 for connector 
disconnection, open circuit, short 
circuit, and poor contact.
Is the connection normal?
Go to step 3. Connect the 
MOB Sensor 
Out J151 to 
the MCU PWB
J415 properly.
3 Check the Yellow color Magnet Roll 
for contamination, scratches, or 
distortion.
Is the Magnet Roll normal?
Go to step 4. Replace the
Developer (Y)
(PL5.2.9).