How to program a key fob for 1999 Cadillac Seville STS?

That needs to be done with the GM dealers Tech2 Scan tool.

Unfortunately there is no "Do it yourself" programming methods.

It should only take them 5 minutes or so.

Also, Verify that the 8 digit part number on the back of the fob matches yours, if not it will not work.

1999 Cadillac Seville Sts

1999 Cadillac Seville SLS V8-4.6L VIN Y

Vehicle Level Accessories and Optional Equipment Keyless Entry Transmitter Service and Repair Transmitter Programming

Transmitter Programming

Notes

REPROGRAMMING RKE MODULE

IMPORTANT: The order that the transmitters are programmed is important, the first transmitter programmed will be transmitter #1, and the second transmitter programmed will be transmitter #2. You can program up to four transmitters. Additional transmitters are available that do not have a number on them. Any previously programmed transmitters which were not included in the programming will no longer function with this receiver. The number on the transmitters are for reference only, #2 can be programmed as #1 or vice versa. Use care to program the transmitters correctly.

Connect a scan tool.

Select diagnostics.

Select body code.

Select body style code.

Select other.

Select RFA.

Select special functions.

Select F0 program key fobs.

Choose the fob number that you wish to program.

Follow screen prompts to complete programming procedure.

Press and hold the lock and unlock buttons on the transmitter being programmed, the door locks will cycle. This should take about 15 seconds .

Continue on to the next transmitter and repeat until all of the transmitters are complete.

Exit the RKE programming and disconnect the scan tool.

Cycle the ignition and test the transmitters for proper operation.

PERSONALIZATION OF THE TRANSMITTERS

The transmitters can be customized to have the following actions take place when a certain transmitter is used:

P/R (perimeter) lighting on at remote unlock

P (park) lamps on at remote unlock

P (park) lamps on at remote lock

Horn sounds on remote lock

To program the personalization features use the following procedure:

Connect scan tool.

Select diagnostics.

Select body.

Select body code.

Select body style code.

Select other.

Select personalization.

Select driver information.

Choose driver.

Select driver number key fob options.

Change functions to active or inactive as desired.

Save options and exit system.

I haven't done one on a cadillac, but what I will tell you to do is to look up the part on the internet and get a really good detailed photo of it, what this will do is tell you what to expect in regards to fasteners and things that might be holding it in place! Next I would say run to your local parts store that carries repair manuals and take a look at one and jot down notes if you don't want to purchase the manual, which is a good investment of 20 dollars I must say!

You need a scan tool like GM's Tech 2 (dealer scanner) or I think a Mastertech will do it too (Some aftermarket facilities use these).

Good Luck!