Horn Not Working

[Monty87ls]

Pretty sure I did a post on this maybe a year ago but I couldn't find it.

04 Sport horns have stopped working. They were working fine and one day I decided to see if they would work on my rav4. I took them off swapped and they didn't work so put them back on the 4runner. Since then they stopped working.

This was probably over a year ago and it was off the road but now back on so I wanna fix the issue. Checked fuses and they are fine, Swapped the relay behind the dash with the one next to it and didn't work. Can hear a clicking when pushing on the steering wheel.

Any other suggestions? Thanks

 

[Offroad Alliance]

all you did was unplug them and transfer to another vehicle then move them back?

 

[FoundedSine14]

Have you checked the grounds? Use a multimeter to verify continuity from this part of the horn to the frame

 

[Offroad Alliance]

Also make sure pins in the connectors arent bent or wires havent come loose. Its a fairly dumbproof system but ive seen where the horn was tied to the radio and some other components so make sure youre fuses are good. Sometimes replace the fuse regardless if it "appears ok"

 

[rdruss]

Have you checked the grounds? Use a multimeter to verify continuity from this part of the horn to the frame

YES. I had a no horn work problem on my Matrix, pulled the ground fastener and it was corroded, but looked ok, replaced it with a fresh fastener and bingo, horn worked.

 

[ArthurKotb]

If you hear a clicking under the hood when you press the horn button on the steering wheel then the relay should be working. Check the voltage at the horn connection when the horn button is pressed. To check the horn, run a jumper wire from the positive post to the horn's connector. (You can also remove the horn from the car and put the connector tab on the negative post and the jumper wire on the positive.)

The relay could be working but still not providing voltage to the horns. It could have a burned connector inside. If you have voltage at the horn connector then the horn is bad.

On an old '91 Camry I had both horns quit at the same time. Sounds strange but they did. I replaced the relay and nothing. I checked voltage at the horn and it was 12.7 vdc. I bought new horns, problem solved.

 

[riceandpho]

horn fuse and go from there, check the wires going to the horn for power like other suggested.

 

[RBLACAUSA]

Mods: Yes...I posted this in 5th gen, too. Please don't delete.

My horn stopped working this past January. 2004 with 141k miles, 2UZFE.

All the controls on the steering wheel work, radio, etc.

I replaced the clockspring with OEM back in June 2023 and everything worked fine from then to this past January, when horn stopped working.

I swapped out both 10A fuses (one in dash fuse box and one in relay box under the hood) and still no horn.

When I push on the horn I hear the relay click behind the dash fuse box.

I have another 4Runner so I swapped out one of the horns with it, and the replacement horn wouldn't honk either, but the horn that I put in the other 4Runner does honk, so I feel I ruled out the horns themselves being an issue, at theast the one on the right side that I switched out.

Using a multimeter, I'm not detecting 12V at the horn plug (unplugged, with POS into the plug and NEG at the neg battery terminal, multimeter set to 20VDC) then the attempt to honk the horn at the steering wheel.

Any suggestions? (EDIT: Fixed, broken wire inside connector at the left/passenger-side horn and they're wired in series, not parallel, 12V goes from left-side horn then to right-side horn, which is why both horn wires showed no continuity).

 

[AuSeeker]

Mods: Yes...I posted this in 5th gen, too. Please don't delete.

My horn stopped working this past January.

All the controls on the steering wheel work, raido, etc.

I replaced the clockspring with OEM back in June 2023 and everything worked fine from then to this past January, when horn stopped working.

I swapped out both 10A fuses (one of dash fuse box and one in relay box under the hood) and still no horn.

When I push on the horn I hear a click by the dash fuse box.

I have another 4Runner so I swapped out one of the horns with it, and the replacement horn wouldn't hink either, but the horn that I put in the other 4Runner does honk, so I feel I ruled out the horns themselves being an issue, at theast the one on the right side that I switched out.

Using a multimeter, I'm not detecting 12V at the horn plug (unplugged, with Pos into the plug and Neg at the neg battery terminal, multimeter set to 20VDC) then the attempt to honk the horn is done at the steering wheel.

Any suggestions?

Possibly the horn relay.

 

[ArthurKotb]

I agree. Check the voltage at the relay, although I don't where that is. It might be the clicking you hear by the fuse box. You've ruled out everything else.

 

[RBLACAUSA]

I agree. Check the voltage at the relay, although I don't where that is. It might be the clicking you hear by the fuse box. You've ruled out everything else.

I ordered a new horn relay yesterday, picking it up today...$100+!!

The horn relay is on the back side of the driver's side fusebox at lower dash. Takes a little work to get to it, but I already did that last night, and unbolted the fuse box. I'll post up the sequence to R&R later today. This AM I'll diso the battery and carefully work out the fuseblock to the point where I can R&R the relay.

In this video the horn relay is already out, but it would plug in directly to the left behind the three other little blue squares (other relays). https://youtu.be/gD60aS9D1ys?si=69cyxSmITUL40J6-

My biggest concern is another poster on a diff forum experienced the same thing on his 2003. He replaced everything inc. clock spring and did everything I've done and also replaced the horn relay and still didn't work, so I'm crossing my fingers and hoping I'll have better results.

 

[RBLACAUSA]

New relay installed, still doesn't work. $100 down the drian.
Insert mad as hell and frustrated gonna bust up some sh!t emoticon here.

Since I haven't seen it posted before, the part number for my '04 2UZFE horn relay was 90987-02022.
In my 4Runner the relay's behind the fuse block are all light grey and not light blue like the ones in the youtube I linked above.

 

[AuSeeker]

New relay installed, still doesn't work. $100 down the drian.
Insert mad as hell and frustrated gonna bust up some sh!t emoticon here.

Since I haven't seen it posted before, the part number for my '04 2UZFE horn relay was 90987-02022.
In my 4Runner the relays behind the fuse block are all light grey and not light blue like the ones in the youtube I linked above.

Sorry to hear, I wish I would of got back here before you went and bought one, especially for that much, that's almost full retail....you could of just swapped one of the other relays to see if it was the relay, usually they are all the same, but in the future, check the number on the other relays and just swap in one of the others before spending money on a new one.

Maybe you can return it??

Or I would have just went to an auto parts store and got an aftermarket one for around $20 to $25.

Also for others reading this if you are ever near or going to a salvage yard for other parts, pull as many relays, switches, knobs etc. as you can for spares, this topic is a prime example of how much these small little OEM items cost even costly for aftermarket parts!!

Also if you can wait for shipping RockAuto sells them for as low as $3/$4 up to around $14 for a Denso relay which sells for $20 to $25 at your local auto parts store.

 

[RBLACAUSA]

Sorry to hear, I wish I would of got back here before you went and bought one, especially for that much, that's almost full retail....you could of just swapped one of the other relays to see if it was the relay, usually they are all the same, but in the future, check the number on the other relays and just swap in one of the others before spending money on a new one.

Maybe you can return it??

Or I would have just went to an auto parts store and got an aftermarket one for around $20 to $25.

Also for others reading this if you are ever near or going to a salvage yard for other parts, pull as many relays, switches, knobs etc. as you can for spares, this topic is a prime example of how much these small little OEM items cost even costly for aftermarket parts!!

Also if you can wait for shipping RockAuto sells them for as low as $3/$4 up to around $14 for a Denso relay which sells for $20 to $25 at your local auto parts store.

Excellent advice! Unfortunately the 4Runner is only going to be with me for a few days before it heads back up north with my kid. I was super anxious to try to get this figured out before he leaves.

 

[AuSeeker]

Excellent advice! Unfortunately the 4Runner is only going to be with me for a few days before it heads back up north with my kid. I was super anxious to try to get this figured out before he leaves.

I know you said you replaced the clock spring but it's very possible that it needs replacing again.

If you try and replace the clock spring, DON'T buy an OEM one they are $260 to $375 depending on where you get it!!

 

[RBLACAUSA]

I know you said you replaced the clock spring but it's very possible that it needs replacing again.

If you try and replace the clock spring, DON'T buy an OEM one they are $260 to $375 depending on where you get it!!

I've really been wondering if it could be the clockspring. But what's making me think it is not is that I can hear the relay click each time i press on the horn. SO with that and all the buttons on the steering wheel working, and no honking at all throughout turning thru full range of motion has me ruling out the clockspring, but maybe I'll go ahead and order a cheapie and try it.

And yes...I did fork out about $260 for that OEM clockspring I bought 3 yrs ago, thinking if the first OEM one lasted me 19 years then the replacement OEM one should, too. :noidea:

 

[AuSeeker]

I've really been wondering if it could be the clockspring. But what's making me think it is not is that I can hear the relay click each time i press on the horn. SO with that and all the buttons on the steering wheel working, and no honking at all throughout turning thru full range of motion has me ruling out the clockspring, but maybe I'll go ahead and order a cheapie and try it.

And yes...I did fork out about $260 for that OEM clockspring I bought 3 yrs ago, thinking if the first OEM one lasted me 19 years then the replacement OEM one should, too. :noidea:

I agree that if the relay is clicking the clock spring is still good, so you're getting voltage to the relay to trigger the horn circuit but no voltage from the relay to the horns, so the horn circuit in the relay seems to be not getting power, I think you need to recheck the fuses and their sockets, check the fuses with a multi-meter for continuity/to see if current goes from one leg to the other while out of the fuse box, sometimes a fuse can be bad even though it looks to be fine, check the sockets with the fuse out to see if you have 12 volts on one side of the socket/s, and then make sure the fuse legs are tight when inserted.

If all that checks out then look for chewed wires, a rodent may have been in there and got the wires going to the horns.

 

[RBLACAUSA]

I agree that if the relay is clicking the clock spring is still good, so you're getting voltage to the relay to trigger the horn circuit but no voltage from the relay to the horns, so the horn circuit in the relay seems to be not getting power, I think you need to recheck the fuses and their sockets, check the fuses with a multi-meter for continuity/to see if current goes from one leg to the other while out of the fuse box, sometimes a fuse can be bad even though it looks to be fine, check the sockets with the fuse out to see if you have 12 volts on one side of the socket/s, and then make sure the fuse legs are tight when inserted.

If all that checks out then look for chewed wires, a rodent may have been in there and got the wires going to the horns.

Did all this (in bold above) yesterday. Going to trouble-shoot at the horn circuit today w/multimeter and a neighbor who's good at that stuff.

Also checked the horns and they work, checked the wire leads at the clips into both horns and they're both dead.

Out of an abundance of caution I did buy a new clockspring on Amazon Prime yesterday and it should arrive today. Neighbor agrees that if the relay's clicking then the clock spring's good but I'm wondering if I should swap it out just to be 100% positive, before entering wiring nightmare. Gemini AI says there's still a small chance it could be a clockspring but perhaps it's hallucinating.

The car is up in the Eastern Sierra now and I was thinking about rodents chewing, too, but so far I've followed most visible wiring closely and found zero evidence.

 

[RBLACAUSA]

FIXED IT!

It ends up that the horn on the left side (when standing in front of the engine and facing in) has two wires feeding in to it. The horn on the right has only one wire feeding into it.
The two wires on the left horn are: one feeding power into the horn connector, then one feeding power back out of the connector and into the horn connector on the right.
In short, the two horns are wired in series and NOT parallel, despite what I read elsewhere, maybe here in T4R somewhere.
Even though we tested the wires for continuity from the relay socket to the connectors to both the left-side and right-side horn connectors and got zero reading, we didn't realize that there were two contacts that we should've tested at the left-side connector. We were about to run a new wire from the relay to the horns when we decided to test for continuity one more time and had the epiphany when I must've touched the second contact while manipulating those wires and got a reading.

From there it was downhill. Simply open up the loom to expose a little more of the wires, cut off the bad connector for the left-side horn and solder on a new 1/4" female flat spade receiver and voila.
We probably could've figured it out if we had a signal tracer and I actually ordered one yesterday but hasn't arrived yet. Oh well. Glad that's over with. It ate up most of my weekend.

So, after 22 yrs of service, I'm guessing road vibrations (the horns vibrate on their single bolt mounts) caused the input wire to become disconnected in the connector.

 

[AuSeeker]

FIXED IT!

It ends up that the horn on the left side (when standing in front of the engine and facing in) has two wires feeding in to it. The horn on the right has only one wire feeding into it.
The two wires on the left horn are: one feeding power into the horn connector, then one feeding power back out of the connector and into the horn connector on the right.
In short, the two horns are wired in series and NOT parallel, despite what I read elsewhere, maybe here in T4R somewhere.
Even though we tested the wires for continuity from the relay socket to the connectors to both the left-side and right-side horn connectors and got zero reading, we didn't realize that there were two contacts that we should've tested at the left-side connector. We were about to run a new wire from the relay to the horns when we decided to test for continuity one more time and had the epiphany when I must've touched the second contact while manipulating those wires and got a reading.

From there it was downhill. Simply open up the loom to expose a little more of the wires, cut off the bad connector for the left-side horn and solder on a new 1/4" female flat spade receiver and voila.
We probably could've figured it out if we had a signal tracer and I actually ordered one yesterday but hasn't arrived yet. Oh well. Glad that's over with. It ate up most of my weekend.

So, after 22 yrs of service, I'm guessing road vibrations (the horns vibrate on their single bolt mounts) caused the input wire to become disconnected in the connector.

That's awesome, hopefully your frustrating conundrum will help others in the future, I hope you can return the expensive parts you bought!!