Walk out to the vehicle with a new battery in the key fob and press the lock AND unlock button at the same time while you stand close to the vehicle for 7 seconds. You will hear the doors go thru a lock and unlock cycle, your fob is now programmed. This will sync existing programmed controllers, security sync. to program new remotes:In the trunk, connected to the wireless remote controller (driver
side on wheel well, need to remove 'mat') is an empty connector with 2 wires connected. short the two connector pins. The locks will all cycle. Press and hold lock/unlock buttons on remote until locks cycle on/off. repeat for other remotes. Remove short across connector pins. Test new remote(s).Warning:existing remotes are deprogrammed, only remotes programmed will work from now on.This worked on my 1998 Cavalier. Be sure battries in new remote(s) are good! Answer
Locate the data
link connector under the dash (under the steering column). Ground out pin #8 of the DLC (top right port) with a jumper wire to any piece of metal close by (I use the e brake hardware). The door locks will then lock & unlock to let you know you are in the programming mode. Simultaneously press & hold the lock & unlock button on one of the keyless entries until the locks cycle (this lets you know the transmitter has been programmed). Repeat this step for your second transmitter. You must reprogram the 2nd transmitter within 60 seconds of programming the 1st one or you have to start over.
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