Question Daughters car, horn won't work. I have been reading posts and collecting information on horn problems. I have determined that hers is not clicking/ticking... I have not found the information of how to find the switch. I understand the location of the horn itself, have checked the fuse it is good. I read something that says there is a "relay" and a "switch" (one and the same?) somewhere... but if it ticks/clicks when you push the horn button the 'relay' is working... can you help shed some light on this ...?
AnswerHi Debbie,
The fuse being good is a good start. It may be helpful though to have a volt meter or if not that then you can buy a neon glow light with two wires that when placed between a test point that you want to verify voltage and any shiney metal surface of the body and if it glows then there is voltage present. Otherwise without one or the other you may be at a loss to understand what is happening. The glow light is available at an auto parts store for a dollar or two.
I would be inclined to go to the horn first and find an electrical disconnect plug. Separate the plug and whether it has one wire or two wires try to measure with the glow light or meter (I'll use light from here on) whether there is 12v at the time your daughter or another helper tries the horn (if one wire measure from it to shiney surface, if two wires measure between the two wires). The horn usually will blowwith out the ignition being in the run position, but nonetheless just in case turn the ignition switch to run but no need to start the car.
If you get 12v on a wire at the plug when the horn is pushed then the circuit is o.k. but either the horn is not working or if you only have a one wire connector then the horn may not be tightly attached to the mounting place because it needs that connection to send courrent back to the battery to complete the ciruit and activate the horn.
So check that, and if you see any other black wires that are related to the horn those are usually ground wires that need to be checked for attachment to the shiney metal. If you do all that and still no sound, then the horn needs to be replaced (junk yard probably less expensive if you can find a Summit to take it from, otherwise a parts store).
If you don't get 12v one or either wire at a two wire plug, then you have to find the horn relay. This might be in a box under the hood with alot of other relays and fuses, but that concept really just began in the early 90's and so their may be no such power distribution center in the car. Rather all the relays for the accessories will be under the dash near the fuses. You might try listening for clicks under the dash when you try all the lights and the wipers and when you hear a click that may be where the horn relay is too. I don't have a Summit manual because I decided not to focus on imports, and I think the Summit is an import.
If you find some relays see if any of them are labelled horn and then if so see it it click when the horn is tried. If it does and you know the fuse is good then you would suspect either relay with defective switch points or a wiring break between the relay and the horn. If it doesn't click then either the relay is bad or the voltage that is supposed to be grouned by the horn button is not getting thru to the relay to make it click. This is often why the horn won't work: the wire from the relay to the horn button is broken (usually near the steering wheel because it gets rotated alot) or the conducting ring in the steering wheel is corroded or worn too thin to maintain the electrical contact. Then you have to remove the steering wheel to correct that issue. Basically, the relay is a remote switch, and the fuse provides the power that the relay controls (sends on to the horn) while the horn button and its wires activate the switch inside the relay. So if the relay doesn't click the activation function is out. It also needs a voltage source (another fuse that is also powering other relays no doubt, not just dedicated to the horn relay) so that shouldn't be the cause of the no click. Rather it is most likely the wire from the relay to the horn button that goes to a copper ring in the steering wheel or the ring itself that is bad. You would need to use the light to check the voltages at the relay but unfortunately I don't have the wiring diagrams to tell you which wires.
This is just a start, I know but it is the best I can do.
Roland
