"TheMajor" wrote in message news:6gx%b.2960$Pc.2401@okepread02...
Craftsman half-horsepower with 3 remotes, lit button inside... NO keyless
entry.

We would like to add a 4th remote. Found a remote that came with the system,
and each time it is set up with it, it cancelles out the other 3 remotes,
and vice versa!

What can be done? Keep in mind that the remote which was found is a match to
a remote which now works along with the other 2 keychain remotes.

TIA for any advice

Sounds like you may have model 51 (or 61) transmitters that have code
switches inside & a learn button receiver. Make sure the switches are
set the same as the matching transmitter (the #9 switch in the key
chain remote is non-functional since it has 3 buttons). Also note that
the switches have three positions +,0,- and make sure they are all set
the same.

If you don't have code switches erase all memory by holding the smart
button until the LED light beside it goes out & then try reprogramming
all four transmitters.

Rolling code (security+) transmitters don't have LED lights so I don't
think it is a case of one transmitter losing it's rolling code
capabilities like some people have had happen.

Doordoc
www.DoorsAndOpeners.com