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E. Engine Control Module EPROM Replacement

*** E. ENGINE CONTROL MODULE EPROM REPLACEMENT

Preparatory Instructions:
The installation of the updated EPROM into the engine control module is a simple procedure.

However, before beginning the EPROM exchange, the following conditions must be provided and the designated tools must be used.

ENVIRONMENT

The work area where the EPROM is exchanged must be free of excessive dust and aggressive chemicals or vapors. A small uncarpeted office within the dealership is recommended. Since low atmospheric humidity promotes static electricity, an evaporating bowl of water can be used to raise the humidity level of the work area.

EQUIPMENT

Screwdrivers (blade type) are only used to open and close the engine control module. The EPROM is exchanged using an IC extractor/inserter set. Tool sets can be obtained locally (Radio Shack, Archer # 276-1581).

STATIC ELECTRICITY

The engine control module can be damaged and rendered unusable by static electrical discharge. For this reason the 3M static protection kit (or equivalent) must be used and properly grounded during the entire EPROM exchange procedure.

EPROM STORAGE

Replacement EPROMs must be stored in the original shipment containers. The label in the center of the EPROM must never be removed.

Procedure:
CAUTION - Whenever connecting or disconnecting any control module the IGNITION MUST BE SWITCHED OFF.





1. Remove the 4 screws (Torx T20) from the cover of the control module.





2. Lay the control module on a static mat and carefully bend up the 6 tabs. Remove the plastic retaining pin using needle nose pliers.





3. Remove the cover from the control module. Carefully separate the upper and lower PC boards and raise the upper board.





4. With a small screwdriver, release the retaining clips located on the right and left side of the connector plug. Pull the upper circuit board out of the connector while applying a slight amount of downward pressure to the upper row of connector pins.





5. Once the upper board has been removed from the connector housing, fold the PC board back and lay the entire module on an anti-static mat.





Remove the protective cap on the EPROM by inserting a small screwdriver into one of the slots on the side of the cap.

6. Remove EPROM by using the extractor tool and carefully pulling it out of its socket.





7. Reinstall new EPROM, making certain that:

^ All pins are straight.
^ The notch in the EPROM and the notch in the socket are aligned.
^ All pins have been inserted into the socket correctly and completely.

8. Reassemble control module by:

^ Reinstalling EPROM cap.
^ Fold PC board over and insert back into connector housing.
^ Snap the upper and lower PC boards back together.
^ Install ground screw for upper board.
^ Place plastic sheet on top of PC board.
^ Carefully reinstall cover making certain that none of the tabs on the cover come in contact with any pins on the PC boards. ***