Programming A New Decoder Module - Cadillac 1991 Fleetwood FWD V8-300 4.9L Service Manual

Programming A New Decoder Module

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New decoder modules are unprogrammed. Before the system will function properly after a new module has been installed, it must be programmed to the code that matches the customers keys.
1. Install the new, unprogrammed decoder module.
2. Insert one of the customers keys in the ignition lock cylinder and turn it to the "ON" position. Start the engine at this time to verify system operation.
3. Observe the security indicator lamp. The indicator should come on and stay on continuously until the next ignition cycle. If the lamp does not go out when the ignition is cycled off and then on again, repeat step 2 thru 3. If vehicle still will not start, refer to diagnostic procedures.