10/003-12 Phaser 790/DocuColor 2006IQ8Initial IssueImage QualityIQ8 IOT Background RAPInitial Actions• Check the end-of-life counter (GP 3) for the Copy/Print Cartridge. If it is at or near end-of-life, replace it (PL 5.1).• Perform VisualCal (GP 16). If this does not resolve the problem, continue with this RAP.ProcedureThe problem is Single Color BackgroundY NRemove the Copy/Print Cartridge. Examine the face of the ADC Sensor. The ADC Sen-sor is clean.Y NGo to the 009-340 RAP to troubleshoot the ADC Sensor Solenoid.Examine the IBT Belt for excessive dirt, damage, or uncleaned toner. The IBT Belt isclean.Y NGo to the 009-704 Belt Cleaner RAP.Remove the ROS (REP 9.3). Examine the ROS window. The ROS window is cleanand undamaged.Y NRemove contaminants using a soft, dry, lint-free cloth. Use minimal pressure whencleaning. If the window is scratched or damaged, replace the ROS (PL 5.1).WARNINGHIGH VOLTAGE!Exercise care when making the voltage check in the following steps.Reinstall the ROS and the Copy/Print Cartridge. Remove the rear cover. Select PrintConfiguration Page from the menu. Measure the voltage from the A terminal on theHVPS to frame ground as the print is processing. The voltage cycles from 0 VDC toroughly -500 VDC.Y NGo to the 009-341 RAP to troubleshoot the BCR bias circuit.Select Print Configuration Page from the menu. Measure the voltage from the C termi-nal on the HVPS to frame ground as the print is processing. The voltage cycles from 0VDC to roughly -500 VDC.Y NGo to the 009-342 RAP to troubleshoot the Developer bias circuit.Replace the IBT Belt (PL 7.2). If this does not resolve the problem, replace the Copy/PrintCartridge (PL 5.1). If the problem persists, replace the MCU PWB (PL 11.2).Check the following:• Check the Developer Roll Spacing (ADJ 9.1) for the affected color.• Check the end-of-life counter (GP 3) for the Dry Ink Cartridge. If it is at or near end-of-life,replace it (PL 6.2).• Access the IOT PARAM SET menu (See GP 3). Reset the toner density for the affectedcolor to the default value (3). Perform VisualCal.• If the problem continues, examine the Developer Housing for the affected color. Check fortoner bridging, uneven brush, or loose High Voltage terminals. Clean, repair, or replace asrequired (PL 6.2).
