I have a skylink 318r keypad with receiver to open my overhead door but dont know code as sellers of the home didn't leave this with - how do you reprogram both transitter and receiver?

Keypad is model 318K
receiver is model 318R
factory setting for keypad PIN is 0000 #
there is no master reset code
you must have the current code to reset the PIN
if you hit the correct code on the keypad followed by the # key - you will get three beeps.
to change the PIN: (current PIN needed)
enter current 4 digit PIN then *
enter new 4 digit PIN followed by *
reenter new 4 digit pin and *
if accepted - backlight will flash and will sound one long beep
takes 2 CR2032 button cells for keypad
you could sit in a chair one night and start at 0000# then 0001# etc until you get three beeps
then use above procedure to change to your desired code
good luck

Push the button on the side of the receiver, then push the button on the remote. That should program the receiver to accept the transmitter. To unprogram all the old transmitters, hold down the button on the side of the receiver until it starts flashing quickly-about 10 seconds.Then program the new one as above. (if this were the old dip switch type, you'd open up the receiver box to read/set the switches)

You might want to look inside the box (can't think of the name that lifts the garage door). it may be written there or be obvious by switches.

Robert