Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Engine Control Module: Service and Repair


When replacing a production Computer with a service Computer, transfer the broadcast code and production number from the production unit to the service unit. Also during replacement, the PROM, CALPACK, and if equipped, the MEMCAL must be removed from the Computer being replaced and transferred to the new unit. Refer to PROM, CALPAK and MEMCAL in this section for replacement procedures.

1. Disconnect battery ground cable.
2. Then disconnect two computer electrical connectors.
3. Remove computer mounting hardware.
4. Remove computer from passenger compartment.
5. Reverse procedure to install.