LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 1987 >> Seville V8-252 4.1L >> Repair and Diagnosis >> Powertrain Management >> Relays and Modules - Powertrain Management >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Service and Repair
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Engine Control Module: Service and Repair


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 and CALPAK must be removed from the ECM being replaced and transferred to the new unit. Refer to applicable heading for replacement procedure.
1. Disconnect battery ground cable.
2. Remove righthand hush panel to gain access to ECM.
3. Disconnect two electrical connectors from ECM.
4. Remove ECM retaining screw, then the ECM and related mounting hardware.
5. Reverse procedure to install.