Horn wire where is it!?

[AmadeusCharger500]

74 charger, which one is horn wire?
Nacho this is a diagram you sent me (thank you very much once again). My car didn't pass inspection just for horn. I checked the horn works nice loud but only blips when pressed on steering column. On 71/72 car horn wire appears to be on engine harness. Doesn't appear to be true for 74 car

[Nacho-RT74]

Several changes allong the years swaping some wires between brakes warning light, starter relay and windshield washer and horn wire. On 74 horn wire is on forward light harness. Wire for horns is green trace red on engine bay since 70.

This diagram is not the correct for 74 though ( attachment name is 73 lights but I think its 72 ? )  since 74 got starter relay wire into the engine harness, being this signal was spliced running to reset button on passenger side of firewall. Maybe I sent it to you just as a reference? If so, I should made the warning about that, Dunno. ( Didn't I ? )
74s got also the windshield washer reservoir wire into the forward light harness.

check for cavity 12, which is the one at a side of the main red wire with the fuse link.

[Nacho-RT74]

bulkhead and firewall wiring disposition for 74s... allways to be checked and confirmed though!!!

Now if you don't have that one on right spot, check for everyone because if you got one wrong, then you got another one swaped around with it!. On 74s the only Empty cavity you can get is the number 3 if A/C car and non tach.

[ACUDANUT]

No Offense, but if your car looks your picture.. No wonder it did not pass inspection. 

[AmadeusCharger500]

No Offense, but if your car looks your picture.. No wonder it did not pass inspection. 

Ha! Guess I should have put the engine and doors on 1st.

[AmadeusCharger500]

bulkhead and firewall wiring disposition for 74s... allways to be checked and confirmed though!!!

Will do, always sound advice from you.

I found out, after much screwing around, that the horn works when the car is on, and only when rpms above 600.  I want to figure this out with the wiring and why its getting feed from Alt and not batt.
However, good news it passed Inspection!

[ACUDANUT]

No Offense, but if your car looks your picture.. No wonder it did not pass inspection. 

Ha! Guess I should have put the engine and doors on 1st.

Doors are on it, in pic's. Glad you got it passed. 

[Nacho-RT74]

bulkhead and firewall wiring disposition for 74s... allways to be checked and confirmed though!!!

Will do, always sound advice from you.

I found out, after much screwing around, that the horn works when the car is on, and only when rpms above 600.  I want to figure this out with the wiring and why its getting feed from Alt and not batt.
However, good news it passed Inspection!

weeeeird

and feed from batt or alt is the same. Both are linked. In fact, the main splice where everything is sourced on your car from factory is actually on alt side of the ammeter, to register the discharge when car is off ( or alt is not enough )

[ACUDANUT]

 TELL YOUR INSPECTOR, Horn broke, watch for FINGER.