The part number for remote key fob is BAB237131-022 and it can be purchased from various places like e-bay and on the net. Match the black remote with the black one. The key fobs are not always interchangeable.
 It is a box like, black in color and has three connectors attached to it. There is a green reset button attached to the right side of it. The ECU can be found under the driver's seat, under the driver's side dashboard or behind the passenger's kick panel., Press and hold the ECU programming switch with a paper pin or some other suitable tool for 3 Seconds. The LED of monitor status will light up for 5 seconds., Press and release top or bottom button of the remote. The status monitor LED light will go off. The piezo chirper will chirp once and so the exterior lights will flash once.

If unintentionally any of the remote buttons is pressed for more than 5 seconds the alarm could go off. To reset the alarm press the top button again.
 Your newly programmed remote should now work fine.
Buy a new key.
Locate the Engine Control Unit (ECU).
Insert the key into the ignition switch and turn it to "ON".
Perform the next step within 5 seconds.
Turn the ignition switch to "OFF".
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