1969 Horn Relay Question
I recently purchased a 69' it appears to have the original horn relay with number 862 on it, but the NCRS judging guide says 69's built after about S/N 9000 used the #890 relay, my car is S/N 17741, is the NCRS judging guide wrong on this one?
-
-
Re: 1969 Horn Relay Question
I don't think we can conclusively say whether the '862 relay on your car is factory original or not. Personally, I would NOT replace it (they're DARN hard to find in decent condition) and simply tell the judges this is what was there...
When you see 'disclaimers' in the judging text like "built after ABOUT..." you're seeing an admission that we don't know EXACTLY when a running change took effect, hence the disclaimer "about".
Typically, design engineers released a replacement part to production and the AIM shows the drawing release date in the ECR block of the AIM page where the part is called out. That simply establishes the EARLIEST date the new part could have shown up on the assy line...
Unless a given change was 'vital' (threat to life, limb, property), assy plant folks were free to implement the change in a manner that was least disruptive and NOT have to purge inventory of the prior part and scrap those still in stock.
So, we typically see old and new parts continue flowing in factory production, intermixed, until the on hand inventory of the old/prior part is exhausted. That's why it's generally tough to put a HARD to document a firm change over date in most of these cases... -
Re: 1969 Horn Relay Question
Thanks for your response Jack, I'll be sure and keep the 862, I've been try ing to get the horns working, the orginals are both dead, this car sit up for a long time in a high humidity area, how do you test a horn relay to see if it is working properly? Your help is greatly appreciated! RichardComment
-
Re: 1969 Horn Relay Question
Look at the cover on the horn relay and you'll see its dual emboss 'S' and 'H'. That defines the function of the connecting terminals that lie DIRECTLY below, on the bottom of the relay case. The cover is dual embossed (S/H) so the annotation works regardless of which position/orientation the cover was installed onto the relay body...
'H' = horn (switched +12V power to the horns). 'S' = switch (contact closure to ground through the steering column to the horn ring contact). For '68 and later cars, there's a third teminal on the bottom that stands by itself. That's the key minder warning buzzer (contact closure to ground to actuate the buzzer).
Simply jumper the H terminal to power you horns and with a jumper wire on the S terminal, touch it to ground. If the relay is working properly, it ought to 'click' and send power out the H terminal. Simple!
One GOTCHA here! The side terminal on the horn relay is the engine compartment's B+ buss bar. It's 'hot' all the time, regardless of ignition switch position. Be carefull NOT to accidently ground this connection or you're going to see SMOKE from the buring insulation on your wiring harness!
The most common reason for horns not to work is faulty grounding at the horn(s). So, if you force the horn relay to trigger (grounding the S terminal) and you don't hear them honk, don't conclude the relay isn't working!
Back up and put a test lead on the H terminal and repeat the test to verify power isn't switching properly before you conclude the horn relay is dead...Comment
Comment