Hello,
the chirp/double chirp on lock/unlock is not audible anymore. The sound was slowly getting quieter and now is almost inaudible.
I am pretty sure that the piezo buzzer (located inside the left fender) needs to be replaced.
However, the part alone is about $60, plus delivery.

I did find one YT video where the poster repaired the buzzer very cheaply, but he said that the replacement piezo buzzer was quieter than the original.

I wonder if anyone attempted this repair and what buzzer (voltage rated) you used- thanks in advance.

I may try to remove the fender liner and test the voltage coming into the buzzer unit; if I do I will update this thread.

 

I'd grab it from the junkyard it would probably be free or almost free. It's the same for all or most Toyota / Lexus cars it seems. My 2002 Highlander one is even the same buzzer. As long as the electrical connectors are the same it'll be fine. Subaru and Honda may share them too. Use eBay pics for comparison

 

Hi MattRX,
Called junk yard near me- they do not carry this part.
Quite a few listings on ebay, probably will get it from them.

thanks