turned on, or if the detected temperature of the thermistors does not rise to a specified temperature for a specified time after the fuser motor is turned on.

Thermistor open: The DC controller determines a thermistor open if:

The detected temperature of TH1 is kept at 12° C (53° F) or lower for a specified time after the fuser motor is turned on.

The detected temperature of TH2 is kept at 4° C (39° F) or lower for a specified time.

The detected temperature of TH3 is kept at 4° C (39° F) or lower for a specified time.

Drive-circuit failure: The DC controller determines a drive-circuit failure:

If the detected power supply frequency is out of a specified range when the product is turned on or during the standby period

If the current detection circuit detects an out of specified current value

Fuser discrepancy: The DC controller determines a fuser type mismatch when it detects an unexpected power supply voltage.

Fuser unit identification

The product detects the type and presence of the fuser. The DC controller detects whether the fuser is installed and its type by monitoring the FIXING UNIT IDENTIFICATION (FSRSNS) signal when the product is turned on or when the right door is closed. The DC controller determines a low-voltage power supply failure and notifies the formatter when it fails to detect the type or presence of the fuser.

NOTE: This product detects if the correct fuser for the product is installed. The fuser from a different product (for example, the HP Color LaserJet CP 3525 Series printer) can be installed in this product, but it will not correctly function.

Fuser unit life detection

The product detects the remaining life of a fuser. The DC controller recognizes a new fuser from the NEW FIXING UNIT (/FSRNEW) signal. The DC controller determines a fuser's end of life and then notifies the formatter when a specified number of pages has been printed after the fuser was replaced.

NOTE: The product detects a new fuser using a fusible link that blows after 100 pages of printing. If a new fuser is installed for troubleshooting purposes, be sure to remove it before printing 100 pages.

ENWW

Engine-control system 17

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HP CP4525DN Laser CC494A#ABA manual Fuser unit identification, Fuser unit life detection