1995 Cadillac Eldorado Owner's Manual - Page 73

The square key is for the ignition only. It has a resistor pellet which is part of the vehicle's P A S S - K ~ ~ system. '~II The oval key is for the doors and all other locks. When a new Cadillac is delivered, the dealer removes the plugs from the key. The plug has a code on it that tells the dealer or qualified locksmith a how to make extra keys. However, the ignition key does not have a knock out plug. The ignition key has a bar code tag attached it. Your dealer or to qualified locksmith, by reading the bar codetag, can then make yourkey. 2-2