Horn Stuck On 2019 Ranger

[matteroffact]

Hit a small speed bump and my horn has stuck on. This happened one other time while off roading but it turned off after a bit that time. Unfortunately this time it will not turn and I had to pull the fuse.

I took off the airbag and the horn switch/clockspring on the steering wheel seem to be fine.
The horn relay makes a click on/off when I press the horn, and same if I swap the relay with the one next to it in the fuse box.

I took the bumper off the get to the horns, and the wire that connects the horns to the harness has a solid 12v no matter the position of the horn relay (on or off). The wire also has 12v if the relay is removed from the fuse box.

What should I try next to fix the horn?

 

[Jim Oaks]

Sounds like the horn may work by grounding it when you press the switch instead of applying power.

 

[Eddo Rogue]

Haha your truck is horny.

 

[Uncle Gump]

The horn is connected to a constant ground source. It comes on when the horn switch sends a ground signal the BCM. The BCM then pulls the horn relay coil to ground to activate the relay. Power is then sent to the horn.

I you can pull the horn relay from the panel and you still have 12 volts at the horn... the horn wire is shorted to battery positive.

 

[Uncle Gump]

Most likely culprit would be a short in the battery junction block or a short in the wire bundle near the junction block.

 

[RumPunch]

Is there some sort of override or another power source possibly from a different controller for the panic function on the key fob? Or security feature.

 

[Uncle Gump]

Is there some sort of override or another power source possibly from a different controller for the panic function on the key fob?

It would have to be an aftermarket control. The BCM handles all that by the looks of things.

 

[Ranger850]

The horn is connected to a constant ground source. It comes on when the horn switch sends a ground signal the BCM. The BCM then pulls the horn relay coil to ground to activate the relay. Power is then sent to the horn.

We've come a LONG way

 

[Eddo Rogue]

I'd listen to Uncle Gump. He seems to be quite savvy with horns and groundings....perhaps also horny...

 

[RonD]

If pulling the Horn Relay doesn't cut off the 12v to the horn but pulling fuse 48(20amp) does, then fuse 48 is getting 12v when it shouldn't

So fuse box short circuit to fuse 48 between relay and fuse

 

[Ranger850]

I'd listen to Uncle Gump. He seems to be quite savvy with horns and groundings....perhaps also horny...

or perhaps well grounded . . .




I'll see myself to the corner.

I know what I did.

 

[Eddo Rogue]

or perhaps well grounded . . .




I'll see myself to the corner.

I know what I did.

The old 3rd leg joke eh? Well played sir.
I am also in the corner.
Your gun is digging into my hip.

 

[Snoranger]

Your gun is digging into my hip.

 

[Uncle Gump]

That isn't his gun...

 

[4x4junkie]

I think RonD has it... There's probably not a lot of wiring length to look over since it looks like both the fuse socket and relay socket are right there in the battery junction box.

Any electrical mods to the truck? (aftermarket lights, switch pods, etc.)?