Horn doesnt work and ive done all i know to do...

[JohnX]

Yes, I would agree.

You should just need to check power coming out of the relay on the green/red wire, and check continuity of that wire.

This is still where you are.

You'll have to locate the wire coming out from the relay (dark green/red). Check for power when pressing horn button. If there is no power, check continuity of that wire ALL the way from the plug in at the relay to the plug at the horns.

 

[4x4JeePmaNthINg]

ive checked continuity passenger side showed .009, driver side was 0. i also tried probing the green/redstripe wire coming out of the plug and didnt get voltage or i didnt have a good probe when pressing the horn, idk.

now if the relay clicks and the wire isnt showing power, where is it likely loosing that connection?

i should be able to remove the relay to mash some wires into the relay socket and hook up the horn to test in the cab right ?

any wiring diagrams for this panel are appreciated, i know with this particular plug out, the jeep doesnt run so its not easy to test.

 

[techno1154]

The horn wire is not ignition dependent so you should have 1 of the large terminals in the relay socket having battery + (positive) at all times. Verify with a probe or volt meter that there is 12 volts there.

If voltage is present, then jumper between the two large terminals in the relay socket. The horns should blow. If the horns do not blow then the problem is the wiring from the relay to the horns,...unless the problem is the horns themselves.

Assuming the horns are single wired, i.e. the body of the horns provide the ground, they are easy to verify operation. Simply run a wire from the battery + terminal and touch the other end to each of the horns. Good horns will provide you with a good wakeup call.

 

[JohnX]

 

[JohnX]

A. Remove relay
B. Verify 12v positive at location 86 and location 30
C. Run Jumper wire from 30 to 87 (horn should sound)
Horn didn't sound? D. Run Jumper wire from 87 to battery positive post (horn should sound)

 

[4x4JeePmaNthINg]

A. Remove relay
B. Verify 12v positive at location 86 and location 30
C. Run Jumper wire from 30 to 87 (horn should sound)
Horn didn't sound? D. Run Jumper wire from 87 to battery positive post (horn should sound)

If I followed this correctly the horn didn't work at either step. Was I supposed to leave the 30-87 jump In?

30 and 85 show 12v, not 86? Fyi horn work when connected directly to the battery

 

[Tbone289]

85, 86 doesn't really matter. That is the coil side of the relay. When the horn button is pushed, 85 or 86 should have 12v, the other side of the coil should have ground.

30-87 jump bypasses the relay.

 

[JohnX]

If I followed this correctly the horn didn't work at either step. Was I supposed to leave the 30-87 jump In?

30 and 85 show 12v, not 86? Fyi horn work when connected directly to the battery

Do you have 12v positive at 86 and 30?

Here's my issue....you said you have continuity on the wire to the horns. You said you have no sound when jumping from 30 to 87. But you didn't say if you had 12v at 30?

Also, did the horn work in step D....where you jump from terminal 87 to 12v positive?


Please be VERY precise in your responses to EACH question. I'm having a hard time understanding what you did or did not do?

 

[techno1154]

If I followed this correctly the horn didn't work at either step. Was I supposed to leave the 30-87 jump In?

30 and 85 show 12v, not 86? Fyi horn work when connected directly to the battery

Since pin #30 is hot at all times and placing a jumper between #30 and #87 which connects directly to the horn and the horn did not sound it leads me to conclude that there is a broken connection between relay pin #87 and the horns. Now come the most difficult part of your trouble shooting,....finding where the connection is broken and it could be anywhere from pin #87 in the relay box to the connection on the horn itself.
If you have the experience and or like challenges, start by removing the fuse/relay box from the holder, (disconnect the battery first) flip it upside down and check that the connector there is good and is seated properly.

Pin #86 is the relay ground which is connected directly to ground somewhere.

 

[4x4JeePmaNthINg]

Do you have 12v positive at 86 and 30?

Here's my issue....you said you have continuity on the wire to the horns. You said you have no sound when jumping from 30 to 87. But you didn't say if you had 12v at 30?

Also, did the horn work in step D....where you jump from terminal 87 to 12v positive?


Please be VERY precise in your responses to EACH question. I'm having a hard time understanding what you did or did not do?

. I have 12v at 30&85, bottom and right side of the relay plug in. 86 is on the left and no it does not have 12v
.i have continuity on the plug to driver side horn plug, passenger side read 009 so it's showing some resistance. As such I hooked the horn to the drivers side to test step C.
.no step D did not work when jumping from 87 to the battery.

 

[JohnX]

. I have 12v at 30&85, bottom and right side of the relay plug in. 86 is on the left and no it does not have 12v
.i have continuity on the plug to driver side horn plug, passenger side read 009 so it's showing some resistance. As such I hooked the horn to the drivers side to test step C.
.no step D did not work when jumping from 87 to the battery.

If the horn didn't sound in step D, then you don't have continuity...as you said you did. Or you don't have functional horns...as you said you did.

 

[Heavyopp]

Try testing with a test light -- If you have a frayed wire, you will still get a full voltage reading, fooling your voltmeter -- for sake of discussion we'll say 12 volts is a full voltage reading

The damaged wire will allow full voltage but not full amperage -- volts carry amps, amps do the work

Use a test light -- Alligator clip to a solid ground -- remove horn relay -- test relay position 30 for incoming power -- Is the light bright? -- yes then go to horns -- No then you have damaged wire between panel inside and PDC

if you are unsure about the brightness go directly to the battery -- check brightness of test light directly on pos and neg terminal of battery

Re-install horn relay

Go to horns -- Find good ground for test light -- disassemble wire connector for horns -- Probe wire in connector plug -- have someone push horn switch -- Bright light on test light?

If yes -- bad horns -- If no -- bad wire from relay to horns



You can also jump the relay -- Remove horn relay from receptacle

Using a short heavy gauge wire, 12 or 10 gauge make a jumper -- Insert 1 end of wire into terminal 30 of relay receptacle -- insert other end of wire into terminal 87 of relay receptacle -- Horns should blow strong -- If not, bad horns, or wire to horns,or ground at horns

Hope this read OK and is understandable -- it's late

 

[4x4JeePmaNthINg]

Try testing with a test light -- If you have a frayed wire, you will still get a full voltage reading, fooling your voltmeter -- for sake of discussion we'll say 12 volts is a full voltage reading

The damaged wire will allow full voltage but not full amperage -- volts carry amps, amps do the work

Use a test light -- Alligator clip to a solid ground -- remove horn relay -- test relay position 30 for incoming power -- Is the light bright? -- yes then go to horns -- No then you have damaged wire between panel inside and PDC

if you are unsure about the brightness go directly to the battery -- check brightness of test light directly on pos and neg terminal of battery

Re-install horn relay

Go to horns -- Find good ground for test light -- disassemble wire connector for horns -- Probe wire in connector plug -- have someone push horn switch -- Bright light on test light?

If yes -- bad horns -- If no -- bad wire from relay to horns



You can also jump the relay -- Remove horn relay from receptacle

Using a short heavy gauge wire, 12 or 10 gauge make a jumper -- Insert 1 end of wire into terminal 30 of relay receptacle -- insert other end of wire into terminal 87 of relay receptacle -- Horns should blow strong -- If not, bad horns, or wire to horns,or ground at horns

Hope this read OK and is understandable -- it's late

I have tested each horn plug side for continuity. driver side showed good, passenger not good.
I have also tried connecting the multimeter to each plug, pressed horn button to check for voltage and no joy.
Ill try the test light for the sake of trying though!

now if the driver side continuity showed good, why when jumped or other wise, fuse fine, new relay, would the horn on supposedly good connection sound?

as shown above we went through some testing steps. I jumped the horn through 87/wire from here and straight to the battery and grounded the horn. shouldnt i be able to simply hook the horn up to the relay socket, horn on the cab floor, or where ever. shouldnt this sound the horn if the relay is clicking. 87 to horn, and ground it to 86 to run the horn straight from the relay socket?
eliminate the horn wiring relay on to the horn plug for testing.

 

[4x4JeePmaNthINg]

If the horn didn't sound in step D, then you don't have continuity...as you said you did. Or you don't have functional horns...as you said you did.

would one side or the other matter though? because passenger shows resistance and driver side read good.

 

[4x4JeePmaNthINg]

85, 86 doesn't really matter. That is the coil side of the relay. When the horn button is pushed, 85 or 86 should have 12v, the other side of the coil should have ground.

30-87 jump bypasses the relay.

so your making sense so far, how do we hook the horn straight to the relay socket to test it? if that doesnt work, i know theres a problem with the socket, and if it does work the horn wires to the horn are bad.

if i simply hook 30+ and 87- to the horn accordingly this should sound the horn no?

 

[Heavyopp]

Yes -- You are jumping the relay if you hook 30 to 87

30 is incoming power for the work load of the relay -- 87 is the load

just a jumper wire between the 2 will connect the line to the load

If you are nervous about doing this you could use an inline fuse holder for the jumper -- This way if something goes terribly wrong you will just blow the fuse in your hand

 

[4x4JeePmaNthINg]

no not nervous, i just want to bypass the horn wiring from the front of the car and put the horn on the passenger floor and plug it into the relay socket to see if it sounds. + to 30 - to 87 and it should sound right?

 

[Tbone289]

What do you mean by + and -?

+ and - of the horn? No, that won't work. 87 is the normally open output of the relay and will do nothing when the relay isn't in the socket.

If you want to bypass the relay and all wiring to the front, then + on the horn to 30 connection of the socket, and GROUND the horn housing/mounting stud. If the horn sounds, this will prove that the 30 pin has a good 12v supply. This should be the same as connecting the horn directly to the battery.

While you're at it, watch this video about how the relay works: https://www.youtube.com/watch?v=FPYRQVANrx0

 

[4x4JeePmaNthINg]

What do you mean by + and -?

+ and - of the horn? No, that won't work. 87 is the normally open output of the relay and will do nothing when the relay isn't in the socket.

If you want to bypass the relay and all wiring to the front, then + on the horn to 30 connection of the socket, and GROUND the horn housing/mounting stud. If the horn sounds, this will prove that the 30 pin has a good 12v supply. This should be the same as connecting the horn directly to the battery.

While you're at it, watch this video about how the relay works: https://www.youtube.com/watch?v=FPYRQVANrx0

yeah im just trying to rule out the wiring as the issue. as stated above i tested and thought i had continuity but then the horn didnt sound so im just:huh:

if i know what u suggested sounds the horn then i can just splice into the plug with the green & red stripe wire and run new wire to the horn plugs.

though, last time i probed the horn wire from the plug with the multi meter i didnt get any voltage when pressing the horn. maybe i didnt probe it cleanly enough idk.

so now im trying to verify if the issue is between the relay and the plug that wire exits the panel from, or the plug onto the wiring to the horn.

 

[Tbone289]

Yeah, I'm a bit confused as to where you are right now, so I'm having trouble helping.


If the horn sounds while the horn + is connected to relay socket pin 30 and horn - is grounded, then you have a good 12V supply to the relay socket.

With the relay in the socket, if you connect the horn + to pin 87 of the relay and ground horn -, push the horn button and the horn sounds, you have a good relay and the horn button is triggering the relay. If it doesn't, then you have a bad relay or the horn button is not triggering the coil in the relay.

If the coil is not being triggered, then you have a lack of ground on one side of the coil or a lack of 12v on the other side of the coil while the horn button is pushed. Coil is pins 85 and 86.

If you determine you have a good relay and the horn doesn't sound when grounded and connected to the wire at the bumper, you have bad wiring between the relay and the bumper.

That pretty much sums up the options.