Has anyone hear of this:

I was having problems with my keyless entry on both remotes for my wife's 2000 LS400 -- I thought they had become "deprogrammed", and no amount of programming seemed to change that (though the car always started properly).

However, after a week elapsed, I noticed that BOTH remotes now unlocked/locked the doors. Then, oddly, a few hours later, they both stopped working again!

My question is simple: is there some sort of antenna connection in the vehicle for keyless entry that could be loose? What other aspect of the keyless entry system could be failing, but then intermittently working?

 

might sound stupid, but did you check the battery inside the remote?

 

Yep. I've replaced both of them twice -- and tonight checked to see if they were still strong (around 2.95v)

Seems unlikely to be a battery -- since the problem affects BOTH remotes at the same time.

 

Some information I've found on the internet suggest some possibilities:

1) Keyless Entry unit (in trunk, behind left side panel)

2) Keyless Entry Relay (not sure if this is the same as #1)

3) 30 amp fuse which says door beneath the left drivers's side near the foot rest.

Any of these might have a loose connection. I haven't found any documentation / repair info on any of these yet. Any pointers?