Advice needed: horn not working

[jhmoore]

2018 TRDORP

No sound at all when you press the middle of the steering wheel for the horn.

When you press the emergency button on the key, the horn does make a sound but it doesn't sound normal.

Watch/listen to video here:
https://www.youtube.com/watch?v=3KEb3CcuDe8&feature=youtu.be

Ideas on what is wrong... where I should start to fix this?

Thanks!

 

[Whippersnapper02]

Do your cruise and steering wheel controls work? If not then it could be clockspring.

 

[jhmoore]

Do your cruise and steering wheel controls work? If not then it could be clockspring.

Yes, cruise and steering wheel controls work.

 

[Whippersnapper02]

Yes, cruise and steering wheel controls work.

Just read what you said about the horn not sounding normal and watched the video. Sounds like the horn is damaged but don't know why the horn button isn't working.

 

[harper7]

Rather then linking
If you google " t4r horn not working"
There are at least 10 old threads on here plus many other websites and at least 4 or 5 youtube videos going through all the troubleshooting

 

[jhmoore]

Rather then linking
If you google " t4r horn not working"
There are at least 10 old threads on here plus many other websites and at least 4 or 5 youtube videos going through all the troubleshooting

Having already done a bunch of searching (which is where I learned to test the emergency button on the key), it'd be super helpful if you would link the one you feel would solve this for me... because I haven't found it yet.

 

[seatia]

Quite probably the clockspring if the horn itself checks out.
All the wires in the ribbon cable have not broken yet, hence why the other functions still work.

 

[[email protected]]

Clockspring. My horn went out with all other controls still fully operational. Wired my horn into my SP9100

 

[jhmoore]

Does clockspring make sense given that when I trigger the horn off the emergency button on the key, the horn sounds kind of weak & sickly (see video link)?

 

[AZrunner11]

Clock Spring / Spiral Cable

Does clockspring make sense given that when I trigger the horn off the emergency button on the key, the horn sounds kind of weak & sickly (see video link)?

It's 100 percent the Clock Spring. It is about $700 for the part ask me how I know.

When my clock spring failed, I could initially turn the steering wheel slightly to the left or the right and it would work. Shortly thereafter it ceased to work.

 

[emmantik]

There's a horn fuse in the fuse block in the engine. Did you check if it's blown or not? This happened to me when I added Hella horns to existing horns. Just a thought...

 

[ArthurKotb]

Does your model have dual horns? I hear just one horn working but if you have only one, then that's normal.

If you have two horns then there should be a harmony between them. I would check the horn relay.

The clockspring is certainly a possibility, but on my '99 Sienna I found that the bearing in the steering wheel column was rusted and not making a good contact. Sometimes I could rotate the steering wheel and the horn would sound, most of the time it didn't work.

I removed the steering wheel airbag, steering wheel, horn contacts and clockspring (be sure to put tape to mark for reassembly). Then I sprayed WD-40 down the shaft. Rusty oil came out so be sure to have something on the floor to keep it out of the carpet. I put everything back together and I haven't had a problem since 2019.

I know it's not the same vehicle as yours, but if you want to replace the clockspring, which is somewhat expensive, you're most of the way there anyway. Try spraying down the shaft to see if you can clean it up. I have a video of my efforts. Don't worry about the contacts unless yours seem to be corroded. The steering wheel bearing is the ground for the horn contacts.

https://www.youtube.com/watch?v=b8g87FX1VBM

 

[jhmoore]

Does your model have dual horns? I hear just one horn working but if you have only one, then that's normal.
If you have two horns then there should be a harmony between them.

I've been reading in the service manual and it mentions a HIGH HORN and LOW HORN--seeming to imply that there are two. But elsewhere is also mentions a HORN and a SECURITY HORN. So I'm really not sure if that's 2, 3 or 4 horns! Trying to figure that out...

I would check the horn relay.

I'm trying to figure out where that is! My best guess from the diagram is that it's actually the panel that fuses 12-15 sit in, but I'm really not sure of that and don't want to go pulling things apart until I'm sure.

 

[Ezlife45]

Look at the schematic above. If you bring +12V to the relay output you should get good power to the relay output. This should check the horns themselves and bring it back to any switches or items that close the relay coil.

 

[ArthurKotb]

On my 2004 SE both horns are right there in front when you open the hood; vehicle left, your right, facing the engine. I would try a jumper wire from the battery to each horn to make sure the horn is working. I had both go out a long time ago on a Camry. Lots of research before I put a jumper wire to them and both were dead. Replaced both and no further problems.

With the motor off, when you press the horn button you should hear a clicking noise. (you may need someone else to press the button. The relay could be under the dash or in the fuse box in the engine compartment.) That's the horn relay. If you don't hear that click then the relay isn't getting any power so it can't engage.

 

[jhmoore]

The fuse: I bought a fuse tester & pulled the HORN fuse. It both looks OK and tests OK. Bummer. Would have been really nice if it'd just been the fuse!

How many horns? I have come to the conclusion that there are THREE. The regular horn is made up of two horns--a HIGH horn and a LOW horn. If you peer into the little opening in the middle of the cover in front of the radiator, you can see both of them. But when I trigger the emergency button on the key, the sound comes from over near the engine air filter. The "SECURITY HORN" must be yet a third horn and separate. According to the manual, pressing the emergency button should sound both the HORN and the SECURITY HORN. "HORN" must be comprised of two actual horns--HIGH and LOW.

See/hear video: Horn not working, part 2 - YouTube

Testing the HIGH and LOW horns--I'm going to see if I can figure out how to remove the cover and get 12V directly to those horns, to see if they make sound when directly powered. Not completely certain how to do that, so if you've got suggestions...

The relay: I am not sure where the relay is. The manual has a diagram but doesn't say where the relay is. It kind of looks like it might be under the four fuses in the corner of the fuse box, but I'm not sure. Anyone know? See attached diagram and pictures of fuse box. Do I pull that black rectangle?? Well, before I pull it, I'd like to just listen to see if I can hear the click, but first I need to know where to listen!

 

[ArthurKotb]

Have you opened the box just to the right of the fuse box you have pictured?
You may be right, difficult to diagnose from a picture. That row of fuses "looks" like it just lifts out of there, but I just can't be sure.

The hi-lo horns should each have a connector going to them. Usually that wire just pulls off from the horn. The horns are grounded to the car so you would just apply voltage from the positive post of the battery to where the connector was. That should blow the horn. Be careful with the jumper wire, don't touch any metal other than the connector tab on the horn

You might want to just find a recommended local repair shop that specializes in Toyotas, or take it to the dealership. If you're not sure what you're doing then you could short out something and have a much worse problem.

 

[jhmoore]

Have you opened the box just to the right of the fuse box you have pictured?
You may be right, difficult to diagnose from a picture. That row of fuses "looks" like it just lifts out of there, but I just can't be sure.

The hi-lo horns should each have a connector going to them. Usually that wire just pulls off from the horn. The horns are grounded to the car so you would just apply voltage from the positive post of the battery to where the connector was. That should blow the horn. Be careful with the jumper wire, don't touch any metal other than the connector tab on the horn

You might want to just find a recommended local repair shop that specializes in Toyotas, or take it to the dealership. If you're not sure what you're doing then you could short out something and have a much worse problem.

Thank you. And, yes, ultimately it will probably be taken to Toyota, but I'm trying to rule out the cheap stuff first because I don't have faith that Toyota won't just sell me a new spiral cable even if all I need is a fuse or relay... I don't have much faith in the Toyota service centers near me... too many times they've tried to sell me expensive fixes that I didn't need.

 

[jhmoore]

Have you opened the box just to the right of the fuse box you have pictured?

I have, and it doesn't look anything like the diagram.

 

[ArthurKotb]

I would agree that you're in the right church on the location of the right part. It's an area I haven't dealt with and I have 2004 T4R anyway so a lot has changed.

On my Sienna, 2 years ago, they wanted ~$200 for a clockspring but I was able to just squirt WD-40 down the steering shaft. I was able to make the horn work from time to time by turning the steering wheel back and forth while holding the horn button. For me, that ruled out the relay and the horns. I Googled the symptoms and found a text only description on how to repair it. That's why I made the video, in case I ever had to do it again.

If you need to replace the clockspring you might check for the part on eBay. I got an ECU module for my Sienna's sliding door there. It was used but it was the newer version of the ECU and half the price of new.

I wish you luck with your efforts. I totally understand wanting to bypass the dealership because of cost. I am lucky enough to have a local Toyota repair shop here. Toyota even lets them do warranty work. They did only Toyota and Lexus cars for many years. Now they will do work on a few other select brands. A good shop, for sure. Check the reviews on shops near you. At least you can get a couple of estimates to compare.