My 2003 Toyota Highlander horn won't work. We took it to the dealer and they replaced a fuse but only the high tone sounds. Then a week later that fuse blew. We have replaced the fuse about 4 times and it keeps blowing! What should I do???

Question edited for clarity.
Question moved to year category.

All those covered by Fuse 23 :>)

Toyota Highlander (XU20; 2001-2007) fuses and relays

Fuse-Box.info https://fuse-box.info > toyota > toyota-highlander-xu2...

The fuse box is located on the left side of the instrument panel, behind the cover to the left of the steering wheel. The location of the fuses in the ...

Toyota Highlander (XU20; 2000 - 2003) - fuse box diagram

Auto Genius https://www.autogenius.info > toyota-highlander-xu20...

Aug 8, 2016 - Toyota Highlander (XU20; 2000 - 2003) - fuse box diagram. Year of production: 2000, 2001, 2002, 2003. Engine compartment.

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Check your fuses for your horn first. I'm not sure if you may have 2 fuses....one for the low and one for the high note. If that checks out ok, it's possible you may have to replace.

If your taillight keeps going out, the problem is the gray connector that the bulb plugs into. Replace that and your problem will be solved. It is difficult to order one from Toyota and get the correct part; the schematic for that taillight is not clear on their computer system.

The most reliable way to get the correct part is to go to a pick-your-own-part junkyard a cut a couple of them out of a crashed Highlander. Should only cost you like $5 each.

This solved the taillight problem on my Toyota Highlander. It took me weeks to chase the problem down. The dealer will charge you hundreds of dollars to troubleshoot the problem. The connectors are easy to change out. You just unplug and replace them.

No 97 high lander

Mine went twice in 600,000 km with the characteristic last gasp sound. Check that your fuse for the horn is ok (in plastic covered fuse block under the hood). If it's blown, replacing it may not work as failed horns can act as a short. Then, I would suggest that you go to a dealer parts department to ask about their OEM horns for your Highlander and to get them to print out the horn placement diagram for the vehicle. You'll see that you have 2 (or even 3) horns. I seem to recall that Toyota wanted over $100 for their OEM horns each. In any case, it was too much. I went to an auto parts store (Napa?) and picked up an inexpensive dual tone universal horn. Under the hood, the collision sensors are close by so best to disconnect the battery to be safe. Now, I replaced the horn on the drivers side -- it's tight to get in there, but you can do it. Connect up the single horn wire (the horn's negative is connected through the mounting hardware). I also disconnected and insulated the wire to the horn in front of the rad (old failed horns can can act as a short). Assuming that your fuse is good, reconnect the battery (and set up your clock and radio stations) and, hopefully, you'll be good to go.

There is a short on the wire connector at the horn itself.

recheck your dome fuse,and check its in the correct position

to my understand this is a dealer item only and not easy to replace it is bolted from bottom,

You need a new horn.