HP LaserJet 4 Service Manual - Page 183

Formatter PCA Removal Caution The Formatter PCA is very sensitive to Electrostatic Discharge (ESD) damage. Observe proper ESD procedures when servicing the printer. Note Before removing the old Formatter PCA, print a 05 SELF TEST to check the current printer page count, if possible. If a self test is not possible, enter the Service Mode, if possible, to display the page count (see "Service Mode" in Chapter 3). Remove the Formatter Cage from the printer before beginning the Formatter PCA removal procedure. After the Formatter Cage is removed, remove the Formatter PCA as detailed on the following pages. (continued on next page) Removal and Replacement 6-29