73 road runner horn doesnt work

[Badsdird]

I am a little baffled about my 73 road runner horn. When the key is on the horn clicks but doesnt beep. When the engine is running at about 1000 rpm and higher the horn works fine. I purchased a new horn and it does the same. I replaced the horn relay and it does the same. Am I missing something? Can someone out here help me out as to what I need to do. Thanks

 

[dadsbee]

.. sounds like you're missing a good battery...

 

[BeepBeepRR]

What dad says or your charging system isnt working. Check your voltage regulator and replace if needed.

 

[Don Frelier]

You shouldn't need the key on?
Pretty sure in 73 the horn would work anytime.
Maybe clean up the ground on the horn.

 

[Nacho-RT74]

Test it sourcing it straight from the battery to know if anything changes

( horn must sound without key, as mentioned )

 

[Badsdird]

Test it sourcing it straight from the battery to know if anything changes

( horn must sound without key, as mentioned )

Thanks for everyones help on trying to get my RR horn working. In the morning I will start checking out everyones input. Thanks again