Removal and Installation Installation of ISS NOTE If the ISS is to be replaced, make sure you remove the APS from the old ISS and, after installing the Grounding Plate, reinstall it on the new ISS. WARNING When replacing the ISS remember to insert the Grounding Plate into the slot as shown (before reinstalling the APS). 8-66 HP DesignJet 5000 and 5500 Series Printers Service Manual