Brother International HL-3400CN Service Manual - Page 162

CHAPTER 5 CONTROL PANEL OPERATION 45-4 CBV TUNE UP This mode should be used when image defects attributed to the OPC belt need to be improved. Adjustment is to alter the OPC belt bias voltage against the reference value 0 (zero) in the range -4 to +4. NOTE: Do not perform this mode frequently. Description of Procedures 1) Press the Continue button after selecting Screen (a) "NVM TUNE UP". (b) (a) -> a) 2) After selecting CBV TUNE UP Code 5, press the Continue button. (b) -> (c) b) 3) The adjustment value can be adjusted in 8 steps between -4 and +4. After selecting a given number, press the Continue button. (c) c) 4) Press the Font button to finish the adjustment work for CBV. (c) -> (d) d) LCD Message 39 FACTORY MODE NVM TUNE UP 45 NVM TUNE UP No.= 45 CBV TUNE UP -+ 45 NVM TUNE UP No.= 5-40