Hi. Im just trying to find the steps on programming a remote lock/unlock key to my 89 celsior. Ive replaced the battery in the key but still not working. Its a key with a little black button on the side which has door lock/unlock written on the back. Thanks.

 

 

There is no "programming" to perform on the North American gen 1 (90-94) LS400 keys. Replacement keys come with a matching ROM chip that inserts into a receiver in the trunk.

 

Where is the receiver in the trunk?

 

Remove the panel where the toolbox is located on the driver's side in the trunk ( various plastic clips and bolts inside toolbox to remove) and the remote ECU is located behind it opposite the trunk hinge.
Also check the switch marked "remote" below the mirror position switch is switched to "on"

 

I've got 3 or 4 one-button remote keys that - as far as I know - came with my '91 LS400 (in-laws were original owners).

One of them works pretty much fine - maybe 20% of the time I need to press multiple times to get it to work, but other than that it is fine.

The others do not work at all as remotes - even with fresh batteries, but they will open doors mechanically and start the car.

Since there is "no programming" does this mean there is nothing I can do to get them to work?

I don't know if they've been through the laundry and electronically ruined or what. They all look fine, except that the only one that actually works is obviously getting fairly worn out.