klyush

Interesting experience: I connected the horns directly to battery (despite alarm was working fine). The sound was low, so something was with the horns or there are 2 relays from alarm and horn itself. Then I changes one horn from another Lexus (I have 2) and it was working fine. So, I removed horns and paid attention that water is leaking from one of them. It appears that horns have minor holes in the body and somehow water was collected inside. I stressed the horns and removed at least some water and connected them back to the battery. They are working somewhat better, but still need some drying. I think the water could penetrate in the horns during high pressure washing.

No, both horns work fine (loud, clear and vibrate) when alarm is in Panic mode.

Just bought a used 2007 RX400H and found that horn does not work properly. It creates a sound, but gives ~10 times less sound than required.

I have cheched the fuse. It's OK. Also, the alarm produces good sound, so the horns are fine. Could it be a relay or switcher problem? if so wehere they located? I have another RH400h where I removed all visible switchers (2 boxes with fuses), but they seems to have no effect on sound.

Any idea? Thanks