How to remove the PROM from the CARRIER

Older GM ECMs do not have removable mem-cals, they instead use a removable PROM and CALPAK assy.  The PROM (chip) is held in a plastic carrier.  This carrier allows the PROM to be removed and installed into the computer without damaging the prom's legs.  The PROM is removable from the carrier by gentle force and use of a small screwdriver.

On the left is the plastic carrier.  Circled in yellow are the tangs that act as small springs which aid in retaining the PROM inside the carrier.  The blue lines represent the leg reinforcements which have small lands on them that "grab" onto the legs of the PROM chip.  To remove the PROM from the carrier, you must apply gentle downward force on the prom chip (effectively pushing it into the carrier) while prying outward on the plastic legs of the carrier.  You can use a small screwdriver to do this; gently push out on the PLASTIC LEGS of the CARRIER ONLY, not the metal legs of the prom.  If you are holding down on the prom adequately,  the metal legs of the PROM should remain straight while you push/bend the plastic legs of the carrier away from the prom.  While holding out on the plastic legs of the carrier, release pressure of the prom and it should pop out of the carrier on its own part-way.  You only need to work one side of the prom/carrier at a time.  Once one side is completely released, the prom should be able to be pushed out of the carrier using the screwdriver without damage to the legs.  If the metal legs of the prom become bent, you can straighten them using the screwdriver or pliers.  BE CAREFUL of static electricity discharge as this can also damage the prom.


The red arrows in the picture depict the no.1 terminal side of the prom/carrier.  When reinserting the prom into the carrier, be sure to orient the notched end of the prom to the notched end of the carrier.  To reinsert the prom into the carrier, simply line up the prom legs with the carrier grooves and gently push down on the prom until you hear a light "snap".  Once the prom is fully inserted, the legs should be right up against both sides of the carrier legs.

If you have any problems doing this please feel free to contact me and I would be happy to walk you thru it.

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