I am trying to find a schematic for the horn circuit in my car (01 mustang gt) to trace it out and figure out why it doesnt work. The horn in my car doesnt work, but when i lock the doors the security system siren chirps ( i assume with no aftermarket security system that the horn beeps when you lock the doors?). also to get under the horn pad, do i just disconnect the battery(due to the airbag) and pull until it comes off (i dont see any screws holding it on the backside)?
01 Horn Circuit
- Thread starter greenlantern77
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Hammer1999Gt
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I have the opposite problem the horn works most of the time but when you lock the doors it doesn't beep anymore
Rusty67
Dirt-Old 20+Year Member
I don't think you want to go pulling until it comes off. Disconnect the battery for sure. I think you need to push down on it and turn it to the left or right. I don't remember exactly how that pad comes off. When I get home I'll check my Ford manual and post with pics.
2000fordstanggt
Member
to remove the driver side airbag ( horn contacts is included in the air bag) you have to remove two plugs on the back side of the steering wheel.. under those plugs is a 8mm bolt on each side.
If the horn works with the factory keyless entry remote then you know your problem has to be with the airbag sliding contact ( clockspring) this is a device that rotates with the steering wheel and allows electrical connection to the horn switch, drivers side air bag and cruise control.. or possibly a broken ye/lg wire circuit #6 before splice #249 this splice is located near the gem module.. so the broken wire if it is that would have to be in the column or in the harness under the driver side of the dash.
Most of the time when a air bag sliding contact goes bad you will also have a air bag light on or the cruise control inop, but sometimes only one system will be inop and the others will work.
If the horn works with the factory keyless entry remote then you know your problem has to be with the airbag sliding contact ( clockspring) this is a device that rotates with the steering wheel and allows electrical connection to the horn switch, drivers side air bag and cruise control.. or possibly a broken ye/lg wire circuit #6 before splice #249 this splice is located near the gem module.. so the broken wire if it is that would have to be in the column or in the harness under the driver side of the dash.
Most of the time when a air bag sliding contact goes bad you will also have a air bag light on or the cruise control inop, but sometimes only one system will be inop and the others will work.
is the sliding contact a slip ring with several contacts (1 for the horn, 1 for the air bag, etc)
"ye/lg wire circuit #6 before splice #249 this splice is located near the gem module.. " ?????????? I have no idea about any of this, what it is or where it is located.
The horn worked before but now doesnt.
I attached a picture of more of what i meant by schematic. If someone had something like this (i dont know if my example is correct or not) that was correct would be great. and if it was something like this but inserted into a picture of the car showing exactly where the wires were and relays and switches and etc (all things involved with the horn circuit) that would be exactly what I was looking for.
Thanks
"ye/lg wire circuit #6 before splice #249 this splice is located near the gem module.. " ?????????? I have no idea about any of this, what it is or where it is located.
The horn worked before but now doesnt.
I attached a picture of more of what i meant by schematic. If someone had something like this (i dont know if my example is correct or not) that was correct would be great. and if it was something like this but inserted into a picture of the car showing exactly where the wires were and relays and switches and etc (all things involved with the horn circuit) that would be exactly what I was looking for.
Thanks
Attachments
See http://cgi.ebay.com/ebaymotors/2004...150813018QQcmdZViewItem?hash=item180150813018
for a picture of what a "clockspring" looks like and where it is mounted.
Years ago, the sliding contacts you describe were used for the horn and cruise control switches. These allowed the steering wheel to spin while the cable to the steering column remained fixed. Sliding contacts were too unreliable for air bags, so were replaced with a long flexible PC board that is anchored at both end, and wraps loosely around the steering column several turns within a housing, in the shape of a spiral. When the steering wheel is turned, the outside diameter of the spiral becomes larger or smaller, depending on direction. It resembles the action of the mainspring in a mechanical clock, thus the nickname "clockspring".
for a picture of what a "clockspring" looks like and where it is mounted.
Years ago, the sliding contacts you describe were used for the horn and cruise control switches. These allowed the steering wheel to spin while the cable to the steering column remained fixed. Sliding contacts were too unreliable for air bags, so were replaced with a long flexible PC board that is anchored at both end, and wraps loosely around the steering column several turns within a housing, in the shape of a spiral. When the steering wheel is turned, the outside diameter of the spiral becomes larger or smaller, depending on direction. It resembles the action of the mainspring in a mechanical clock, thus the nickname "clockspring".
thanks for the reply, i cant get a good view from that pic though(probably becuase i dont really know what im looking at/for). Are there any pictures that would show how the whole horn circuit works from the horn that you push on the steering wheel to the horn that sounds under the hood and everything inbetween showing how it is connectect electrically and where it is located physically? thanks
I am not aware of any single picture that shows both the circuit and physical location of components as you described. The example you posted pretty much applies to all cars. In the Mustang, the points marked "5V" and "24V" connect together then to the battery (+12V) through a fuse. Other than that, the only difference is the connections to the both ends of the horn switch are routed through the "clockspring" cable. Servicing the clockspring is an involved project, as it is mounted directly behind the steering wheel. Both the driver airbag and steering wheel must be removed to access it. I would want to be 100% sure the clockspring is bad before attempting this repair.
Check your owner's manual. On my '03, pushing the remote "lock" button with the dorrs already locked beeps the horn. If that function does not work, the problem may be elsewhere. Does your cruise control turn on and off, and actually control your speed? It shares "clockspring" wires with the horn circuit. If the cruise control works, the "clockspring" is not the cause of your horn problem. I think the fuse and relay are more likely to fail before the horn switch and "clockspring".
Check your owner's manual. On my '03, pushing the remote "lock" button with the dorrs already locked beeps the horn. If that function does not work, the problem may be elsewhere. Does your cruise control turn on and off, and actually control your speed? It shares "clockspring" wires with the horn circuit. If the cruise control works, the "clockspring" is not the cause of your horn problem. I think the fuse and relay are more likely to fail before the horn switch and "clockspring".
i dont have the factory remote (which was going to be my next post). I have a "much better" system with alarm and autostart (the alarm is a pain in the ass and drains the battery and i dont plan on driving the car in the winter so the autostart in only a novelty). So when i lock the doors the siren chirps but no horn. If i assume that the horn is the problem, Should i be able to hear the relay in the fuse/relay box under the hood if i am pressing the horn inside the car? Also can i just hook the horn directly to the battery to see if it works? And where would the horn be. Thanks
Your aftermarket alarm may not be connected to the horn (no need, since it has a siren). This makes it useless as a diagnostic tool. Do you have a cruise control with on-off and resume-set-cancel switches mounted on the steering wheel?
Does you air bag self-test indicator come on when you first turn on the ignition, then go off after a few seconds?
Both the driver air bag and cruise control share "clockspring" wires with the horn circuit.
Does you air bag self-test indicator come on when you first turn on the ignition, then go off after a few seconds?
Both the driver air bag and cruise control share "clockspring" wires with the horn circuit.
Here's the wiring for the car including the horn circuit.
http://rapidshare.com/files/51943828/Wiring.zip.html
http://rapidshare.com/files/51943828/Wiring.zip.html
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