Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1989 Cadillac Seville BaseFACTORY OEM SERVICE PROCEDURE
EEPROM Replacement Procedure
- Remove instrument panel compartment door. Detach and move aside the relay bracket assembly and fuse panel. With ignition off, disconnect BCM harness connector. Loosen BCM-to-bracket retaining nuts. Remove the BCM.
- Remove 4 screws from EEPROM access cover. Remove cover. Using rocker type PROM remover, engage one end of carrier and press on vertical bar end of remover. Rock engaged end of EEPROM carrier up as far as possible. Engage opposite end of carrier and repeat process until EEPROM carrier is free of socket.
- Carefully install new EEPROM (mounted in carrier) into BCM socket while aligning small notch in carrier with small notch in socket. Press on EEPROM (carrier only) until EEPROM is firmly seated in socket. To complete installation, reverse removal procedure.
- Enter diagnostics and clear BCM code or codes. Start engine and observe odometer display. If "ERROR" continues to display, and EEPROM is properly installed, replace BCM.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.