Finally, I was able to program my 2004RX to my Chamberlin opener (just moved in). I had lots of issues and tried many times, reading the threads on this site and looking at a homelink web.
Here was my problem. My RX already had the 3 buttons already programmed to other devices and I was trying to re-program both my cars to our newer home. Will not work. If, as in the documented step 1 of the book, you press the homelink and remote together and the blinking visor lite is rapid, you are out of luck! The directions indicate that a slow blink will turn to rapid....mines never had a slow blink on any of the 3 button sets. I did not get a slow blink even when I just pressed the 3 buttons. (However, after the memory reset, the same 3 button went to a slow flash....I knew something was different)
So, I decided to erase the entire homelink car memory by depressing the outside 2 buttons. Hold down both for about 20sec. When the steady lite flashes rapidly, all codes are gone. I really was hoping for another way since one of my buttons would have still been good. There is no way that I know to only erase a selected button, just all of them.
Next, since I knew my opener had a rolling code (the book said to look for a flashing lite that eventually goes steady) I had to depress the "learn" button. The button has a lite go on and you have about 30sec to go to the car an press the same homelink button again. Hold it down till the flashing lite goes to solid. My opener did a flash too on this first press, indicating that something took hold. I then depressed the button a 2nd time and when the homelink lite went solid, the garage door started to close. WORKS! I did not require a 3rd time button depression.
The key is whether the system allows programming. First, the homelink is alligned with the remote, next the garage opener is hooked up with the homelink. DO NOT press the "learn" button and the garage remote together UNLESS you are trying to re-program the remote opener buttons to sync up with the actual opener. (You may require to do this after doing the cars.....I did because I had 2 doors being operated by 1 remote...the 2nd remote button did not remember the 1st opener), If you have the rolling code, only the homelink button is pressed 2 times (some of you may need 3rd time) after pressing the "learn" button. Also, hold it down till the flashing light goes to steady, not just a press 2 times. If the opener doesn't blink (if you got bulbs in it) or if you don't hear a sound like a blink, your programming did not work.
Determine if your car already has a full set of 3 programs. If a new car, that should not be a problem. Press a homelink button and you should just get a steady blinking lite vs. a rapid blink (that is what happend after I reset all whole button set by pressing the outer 2 and waiting 20sec till the lite flashes)....Really works
