I have a dealer installed 1 channel remote starter that works fine. The problem I have is that when I turn the engine on with it, the original remote cannot open the doors. The RX does not have keys, so the only way to get in the car is turning the engine off with the remote starter, and then use the original remote.
Is it possible that the implementation is so flawed, or there is a way to reprogram the original remote?

 

You're original remote has a door/glove box key. You just remove it from the remote by pushing the spring loaded release. It's so you can lock your glove box and give a parking attendant the fob to operate the car.

 

What type of remote starter was installed? The factory one shouldn't do this. Sounds like an cheap aftermarket device or screwed up install is your problem.

 

The flawed one?

I thought the Lexus genuine remote starter will shut off the engine after the certain mins OR when you try to enter the RX. I thought Lexus specially designs this way... !?

 

https://www.clublexus.com/forums/rx-...-question.html

Check this one. There are some complaints, details, discussions, etc... this may explain a little more about what the Lexus genuine remote starter can do or cannot do.

 

I have a dealer installed remote branded Pursuit. I got it as "freebie" and deal sealer.
Talking about remotes, how many original remotes are supposed to come with the new Lexus. I got two.

 

Only two remotes come with the car. So you have an aftermarket remote starter installed by the dealer.

That throws out the links RXETS suggested. I still stand by my first comment.

More to it, theres probley a compatibility problem that may not be able to be fixed.

 

I guess you're right.