Another Horn Problem - Doesn't Sound When Grounded

[vamram]

I've been trying to get the horn on my '72 Super working for a while now. I've replaced the turn signal switch w/an original German one. The after market one had broken inside (plastic parts and metal spring had popped out) and I thought this may have been the reason for the horn to stop working.

After replacing it I still don't have a horn. With the ignition key on, I have 12 volts at the horn terminal w/the black wire. I thought maybe the ground wire is bad somewhere. The ground arms on the switch have good contact w/the horn ring on the steering wheel. I figured something's up w/the ground circuit so I tried bypassing the 2nd wire. I disconnected the ground wire from the horn and put a test light on it, turn on the ignition and grounded the test light thinking the horn should sound. Instead, I get this -

The test light turns on but the horn does not sound. Does this mean that the horn is bad?

Thanks,

Victor
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'74 Super 9/16 - present, in refurb process.
'73 Super - 6/18 - Present - Daily Driver!
'75 Super Le Grande...waiting it's turn in line behind '74.
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[AlmostHeavenWV_VW]

V,


I think it's dead
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1973 Standard Beetle
1600DP AK case
Solex 34PICT3 Carb
Bosch DVDA 205AJ Distributor

[vernonc]

It can, usually, be fixed. There's a set of points inside that must 'make and break' causing a vibrating of the diaphragm. You'll need to clean the points and, maybe, re-adjust.

Hope this helps.

mort
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'69 sedan, low mileage, all original.....currently being 'freshened-up' for road trips and daily driving...just not every day

Freshening-up link http://www.thesamba.com/vw/forum/viewtopic.php?t=617386

[vamram]

As I feared...Is there a recommended way to open it..?
_________________
Eventually, "we are what we pretend to be.’”
Give peace a chance - Stop Russian-Soviet Aggression!!

'74 Super 9/16 - present, in refurb process.
'73 Super - 6/18 - Present - Daily Driver!
'75 Super Le Grande...waiting it's turn in line behind '74.
Click to view image
Save the Supers!!

[vernonc]

[kreemoweet]

It looks to me like you have the test light in series with the horn. The current thru the test light is nowhere near enough
to sound the horn. You need to jump with a plain wire from the horn neg terminal to a good chassis ground. If the horn is
good, it should sound, if the pos terminal is hot (which it should be if the ign switch is turned on).
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[Cusser]

[vamram]

Ok, thanks for the pointers. I ran out of time (and energy) today - tons of spring clean up yard work to keep wifey happy! I'll try w/a solid wire, no test light, in the a.m.
_________________
Eventually, "we are what we pretend to be.’”
Give peace a chance - Stop Russian-Soviet Aggression!!

'74 Super 9/16 - present, in refurb process.
'73 Super - 6/18 - Present - Daily Driver!
'75 Super Le Grande...waiting it's turn in line behind '74.
Click to view image
Save the Supers!!

[vamram]

Ok, well that was a wake up call. I did the separate wire test and the result is that the HORN IS FINE. PRACTICALLY BLEW MY EARS OUT. Sorry, was i shouting?

So...perhaps my original old German turn signal is no good?
_________________
Eventually, "we are what we pretend to be.’”
Give peace a chance - Stop Russian-Soviet Aggression!!

'74 Super 9/16 - present, in refurb process.
'73 Super - 6/18 - Present - Daily Driver!
'75 Super Le Grande...waiting it's turn in line behind '74.
Click to view image
Save the Supers!!

[Cusser]

[vamram]

Yeah, fun alright. Should the copper arms on the turn signal switch read 12v w/the ignition in the ON position on a '72 switch? [EDIT] It reads 0 volts. But there is 12v on the green wire of the harness jack that connects to the switch. Is the switch bad or am I still chasing a ground? Or do I have a the wrong switch for a '72?

(credit to Samba gallery search for the pic).
_________________
Eventually, "we are what we pretend to be.’”
Give peace a chance - Stop Russian-Soviet Aggression!!

'74 Super 9/16 - present, in refurb process.
'73 Super - 6/18 - Present - Daily Driver!
'75 Super Le Grande...waiting it's turn in line behind '74.
Click to view image
Save the Supers!!

[sb001]

It's just a grounding issue. You already know that when the horn circuit is properly grounded your horn sounds thanks to the test you did. So your issue lies in the ground circuit somewhere after the horn. So it's either in the wiring from the horn to the steering wheel, OR it's in the horn button itself not making proper contact with the ground points inside the steering wheel when you push on it. So check to make sure the BROWN wire is connected to your horn button properly. (Green wire shouldn't have anytihng to do with the horn, I believe it's for the windshield wipers looking at the 72 wiring diagram.)
Be aware also that the brown ground wire coming off the horn goes through one of those plastic connectors inside the trunk on its way to the horn button, probably located somewhere up around the dashboard. Make sure one or the other side hasn't come loose there.
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1969 autostick sedan, family owned since new
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[vamram]

[ashman40]

Hope you have a multi meter that can read resistance. Set the meter to read ohms (lowest ohm reading your meter can handle) then run the following tests. You are trying to find the section of the horn ground circuit that has resistance, or is disconnected. By grounding one end of the wire and testing along the circuit hopefully you can find where there is either a disconnect or a large resistance (greater than 1ohm).

At the horn, disconnect the ground wire and wire your meter between the end of the ground wire and a good ground point. Have someone press the horn button. You should get a near zero ohm reading (direct short to ground). Definitely less than 1.0-ohm. If you read a resistance greater than 1.0-ohm you have a bad connection somewhere in the path to ground.

Go to the junction below the steering column. Disconnect the ignition/dimmer switch/horn plug from the turn signal switch pegs. Before you do this, ID which peg is the horn ground wire (should be a brown wire in the plug). The later beetles had two brown wires, one for the horn and one for the ground leg of the dimmer switch. Make sure you confirm which is the correct brown wire. Test the peg that connects to the brown horn wire for ground the same way you did the horn wire. When you press the horn button it should show zero resistance to ground. If the resistance is much higher than 1ohm work your way towards the ground.

Reconnect the plug below the steering column. At the horn, ground the end of the ground wire (red one in your pic?). Remove your steering wheel and test the "brass ears" in your pic for resistance to ground. Since you grounded the horn end of the wire it should show zero resistance to ground. If there is resistance in this leg of the circuit you need to clean the wire ends. Maybe even snip the end of the wires off and crimp new ends with clean connection to the wire.

Re-install the steering wheel but remove the large horn button. Find the wire that comes from the horn ring that make contact with the "brass ears". The horn ground wire is still grounded at the horn. Test the end of this wire for resistance to ground.

At this point, you need to ID how your horn button is grounded. '71-earlier had a ground wire coming out the center of the steering shaft. I'm not certain how the '72 horn button was grounded. I think the steering shaft itself is grounded at the steering coupler with a jumper wire connecting the shaft bolt to the steering box bolt (the steering box being grounded). Test the shaft for resistance to ground.

All of the above tests look to the circuit path and test for resistance. The horn ground circuit should have a zero resistance path to ground when the horn button is pressed. Once you ID where the disconnect or resistance in the circuit is located, clean up the wires or connectors until you get a low resistance circuit.
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AshMan40
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