About a week ago my remote transponder stopped locking and unlocking the doors on my 2001 LS430. My first thought was a dead battery, but I noticed that the red light on the remote still flashed when I pressed a button. Also, all the doors and trunk open when I manually use the key, so I don't think it's an actuator problem.

I went to Home Depot to get a replacement battery and there was a car remote/transponder tester at the battery display. According to the tester my remote (with current battery) was working fine. I did not get a new battery because at this point I'm not sure that is the problem.

I searched online but cannot find an answer to this problem for my specific vehicle. One suggestion I did find was to check and see if the switch that controls the remote operation (down by the steering wheel) had been turned off. That was for an LS400. I cannot locate a similar switch inside my LS430.

So, before I take it to the dealer I want to see if there is a simple solution, or at least a way to accurately diagnose the problem so I know exactly what it is.

Any help or suggestions will be greatly appreciated.

Thank you,
John

 

Have you checked fuses (circled in red below) for the wireless door lock system?

 

Thanks for the reply rkw77080. I checked the four fuses you circled and they were all ok.

Do you have any other suggestions?

 

OK, so I decided to go ahead and buy a battery just to positively rule that out and, you guessed it, the problem was just a dead battery.

So I learned that, A. don't trust the transponder tester at the battery display, and B. NEVER assume anything. (you think I would have learned that by now).

Anyway, thanks again to rkw77080 for your assistance.

 

Good move, jgrooms! Congrats for the fix...