Engine Control Module: Service and Repair

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When replacing a production ECM with a service ECM, transfer the broadcast code and production number from the production unit to the service unit. Also, during replacement, the PROM or MEM-CAL must be removed from the ECM being replaced and transferred to the new unit. Refer to PROM Or MEM-CAL, Replace for procedure.
1. Disconnect battery ground cable.
2. Disconnect two ECM electrical connectors.
3. Remove ECM mounting hardware.
4. Remove ECM from passenger compartment.
5. Reverse procedure to install.