2008 HP Color LaserJet CM2320 MFP Service Manual (P/N CC434-90969)

• Covers the HP Color LaserJet CM2320 MFP Series, including CM2320nf and CM2320fxi, in a 410-page PDF of HP service publication P/N CC434-90969, edition 1, September 2008.
• Factory removal and replacement procedures cover the fuser, intermediate transfer belt (ITB), and color-misregistration sensor assembly.
• Paper-feed repair covers Tray 1 pickup-roller and separation-pad replacement, plus pickup and separation rollers for Trays 2 and 3.
• Scanner assembly, control-panel, and ADF pickup-roller replacement are documented alongside copy- and scan-quality troubleshooting.
• Electrical service covers formatter, fax, DC controller, and high-voltage power-supply PCAs, with model-specific connector references.
• Diagnosis includes color calibration, internal print-quality test pages, control-panel and event-log fault tables, plus fax tests and T.30 protocol traces.

Fax, Memory-Card, and Duplex Configurations

The parts tables distinguish CC434 base, CC436 Fax, and CC435 Memory-Card bundles. The Memory-Card model adds automatic duplexing, memory-card slots, and Tray 3. Separate rear-door and cover procedures address the different simplex and duplex chassis.

Repair coverage is field-replaceable-unit (FRU) removal and replacement, not component-level repair. The laser/scanner is not a replaceable FRU under this service approach. The transfer roller is serviced with the paper-feed guide assembly rather than as an individual replacement part.

Theory of Operation and System Architecture

The manual details the engine control architecture, laser/scanner unit, image-formation stages, and pickup-and-feed mechanisms. Its sequence-of-operation table distinguishes the WAIT period and standby (STBY) from initial rotation (INTR), active printing (PRINT), and last rotation (LSTR).

The DC controller circuit diagram and Fuser control circuit relate the operating sequence to the control hardware. Scanner coverage explains the CCD optical system and sensor operation, supported by ADF paper path routes during duplex job.

Assembly Replacement and Post-Repair Checks

Beyond rollers and cartridges, the removal chapter covers the drum and developer motors, fuser-motor assembly, duplex-reverse drive, and paper-delivery assembly. Reinstallation notes address gear and spring positioning, cable routing, and chassis engagement. Post-service procedures check print, copy, and fax quality after a repair.

Replacing the formatter and DC controller together can erase their shared NVRAM configuration and cause severe print-quality problems. The fuser procedure also flags a fragile connector guide: excessive force can damage it and require replacement of the entire fuser.

Fault Isolation and Service-Menu Tests

The Repetitive image defects table links repeating marks to the responsible roller, drum, fuser, or belt assembly. The DC controller connectors reference pairs connector faults with recognizable messages and startup symptoms. A product-level Circuit diagram provides wiring and interconnection detail.

Secondary service functions include Scan Calibration, Display Test, and Button Test, along with Clean Belt and pickup-roller positioning. A separate recovery procedure addresses corrupted firmware downloads using a Windows computer and USB connection. NVRAM initialization and USB/network troubleshooting are also documented, while memory-card fault tables address missing files and proof-sheet printing or scanning problems.

Specification and Assembly Data

The engine control documentation outlines electrical parameters for the DC controller and the power supply unit. Overcurrent and overvoltage protective functions are clearly defined. Fuser-control theory identifies the main thermistor (TH801) and thermal fuse (FU1), with protective thresholds and failure-detection conditions.

Exploded assembly views and alphabetical/numerical parts lists distinguish the 110–127 V and 220–240 V fusers and Americas/Asia versus European fax cards. Physical and environmental specifications sit alongside media-registration, image-placement, and duplex-alignment tolerances.

Internal repair involves high-voltage circuitry and a hot fuser. Follow the manual’s electrical-isolation, fuser-cooling, ESD, and laser-cover precautions before parts removal.