How to test if the relay is blown?

The horn is working since I teasted it with a long wire from battery.

Who sells those for 1973...not ZIP...not Ecklers...

 

The reds must be hot ,
ground the black wire terminal(wire comes from horn button in column),
this should put power to the green wire terminal going to the horns.

The pink is for that dang annoying key buzzer.

edit-relay--do you need it to be correct,if not an $8 relay from a 78 can be wired in with only 1 wire additional over to the terminal with all the red wires

 

I thought I'd search the forum before I posted a new thread, so I'm not trying to hijack yours. But this is coincidental. I just tested the horn in my '72 which works with a hot jumper wire. When I press the horn button, the relay just clicks. The positive post on the relay is hot. And the dark green wire is connected from the relay to the horn. So I figure the relay is bad.

 

Pull the green wire off at the horn and use a 12v test light , watch the light when the relay clicks,if it doesnt light then your correct the relay is bad. You can try removing the cover from the relay and cleaning the points.

 

Thanks for the dose of common sense. I just went back out and tested the green lead to the horn from the relay ... and it's dead. That makes 2 of us either trying to fix a relay or looking for a new one.

 

Milloin thanks allready, but some questios/comments to be sure I do the right thing...
1. First of all definitely I do not need to be correct so if you can explain like to a not too clever guy how to use and wire the 78 relay into this setup I would love the help. And what relay it is from 78, is it the 78 horn relay or some other relay?
http://www.ecklers.com/product.asp?p...4&dept_id=1723
That one?
2. yes all the reds are hot all the time.
3. "ground the black wire terminal" should I have the ignition from car key on or off when doing this or is that irrelevant?
Also is it so you mean with BLACK the wire that seems to come from the same bunch of wires like the green wire? Not the black one being in the middle of the 3 hot wires.
And grounding it does it mean I disconnect the black wire from the terminal and the use a separate wire to conncet that empty terminal in relay and any solid ground point in the car? And them I measure with a testingpen with light if the green wire at the horn end gets power?

Is the pink one of the 3 hot wires? the one paired with the small black? I think I have not a functioning key buzzer since I never hear any alarm whatever position the key is...

Best regards, Vesa

 

I took the black wire/connector off and put a wire inside that terminal and other end to a ground point and it horns! so the relay is good? and the problem is somewhere between the black terminal and steering weel horn button...it does not give ground signal to relay when pushing the horn button, I figure...

 

You are correct. Your problem could be in the wiring or the column. Easiest way to find out is under the column is a long connector (harmonica connector) the black wire passes through there , seperate the connector, find the correct black wire on the side opposite the column and ground it, if the relay clicks and blows the horn then you can move into the column-next check out the horn button switch.
The black you need in harmonica conn the should be between the double light blue and the pink with black stripe.

Sorry I didn't answer sooner I'm working on an old Chevelle conv top hydraulics.

 

Thanks again!! I will go that route in my investigations. I will be on business trip for 2 days but after that I will report how I progress.

Today I checked that there is ground in the column main shaft (upper end of it) and also the plate that the horn button presses has ground so the problem is deeper..

 

Thanks Roger. I pulled the relay cover off and just scraped and sanded the tiny contact points in there. It was easy. The hardest part was trying to remove those 2 bolts and rubber nuts that mount the horn relay to the inner fender! After 38 years, they've seen better days. But the horn works now! Good luck with your ground wire issue Vesa. It sounds like you're close to fixing it.

 

It was the spring loaded button that is supposed to touch the plate the horn button pushes when pushed. It was jammed too deep and never contected the plate.

Also when the steering column 4 bolts were off and the issues was solved still sometimes it worked and sometimes not...depending on the position of the column. It must have been some connector or some wires somewhere...never found out, but anyhow I found a position when bolting everything up now all works...

 

i have the same problem. i just tried to clean the relay, but it still dosn't work.

it works sometimes... if i honk the horn 10 times in a row, it's possible that it sounds one or two times.
other than that, the buzzer never worked (which is actually fine with me, but i need the horn)

The horn is new, i bought a new one thinking that it was the problem, but apparently i need a new relay.

where can i find the same relay?? 1973 corvette...

 

1972 & 1973 take the same horn relay. They're on ebay. I almost bought one there before I repaired mine. You may need to use a set of vice grips on the inner wheel well, to hold the rubber covered nuts in order to remove your old one. I did. It was tough. When the screw was only slightly loose, I had to pull both of those rubber studs out of the holes. Replacement rubber studs and screws are on order.

 

If they are scary expensive don't forget you can use a late model horn relay with the temporary addition of 1 red wire and then hide the small relay under the fender.

 

http://cgi.ebay.com/ebaymotors/CORVE...#ht_4856wt_939

45 dollars??? WOW!

 

Advance auto parts tells me that i can use this for the 73 corvette....

http://shop.advanceautoparts.com/web...CGRP2020A____#

but the connectors are totally different.

 

I can't see that relay clearly but if its 3 prong all your going to do is pull the black and green off your old relay and put them on the new relay,then you have to run a wire from the 3rd prong on the new relay to the stud on the old relay with all the large red hot leads.(leave the old relay where it is)
If your going that direction I will get you a diagram of where the black and green go on the new relay.

 

i guess i can try since that relay it's 6$... it's worth to try.

would you?

 

Couldn't find a diagram that I'm "allowed" to post here is a picture with colors on each spade. This is a stock 78 Corvette horn relay and might be best if thats what you buy. If the relay you buy is different from this one the relay will have a tiny diagram with it showing how to connect.

 

ok. Basically i connect all the reds on the red one (also the pink one?) and green and black on the other 2.

I'll try... i hope to don't blow the car (i already saw some sparks yesterday . i'd just forgotten to unplug the battery)