snowway

(Background)
Been diagnosing my cruise/horn problem for a while now. Haven't swapped the clockspring yet, but have the part coming. Meanwhile, I have been following the procedures in the service manual and got to the horn diagnostics. First, I squaked the horn via jumpers. Then verified Fuse #7 is good and I do have voltage. Next was to pull the horn relay and testlight pin 1 and 3: No light. I have continuity, but no voltage. I pulled the junction box apart and the YE/LB wires are all good from fuse to relay, just no voltage. There is no click from the relay when the horn is pressed.
(Question)
Since the service manual only says to check the circuit at this point... does the clockspring have to be operational to be able to jumper the horn from the relay terminal? In my mind, it should work when jumpered regardless of clockspring activity, but there is a ground within the clockspring circuit (G200) that would maybe make sense to prohibit proper operation...
1999 F150 XL 4.6 4x4

RLXXI

The clock spring simply provides a ground for the relay. Perhaps this schematic will help.


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snowway

Well, the fuse connector was not seated within the junction box correctly. So now I get 12+volts at the relay pin 1 and 3. Since I am unclear of jumpering within the relay connector, would it be jumpering pin 3 to pin 5 to get the horn to squak. Looks this way in the diagram...

RLXXI

Correct.
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snowway

That squak'd... I may have pooped a little when it did.. So looks like the horn switch or most likely the clockspring then since CC doesnt work either...?

RLXXI

Clock spring was the most common problem when I was working at the dealer. Horn, air bag, CC all or any combination would fail. Be careful changing it, it should have a plastic lock tab to keep it centered so that it don't get wound too tight and break when driving.
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snowway

Changed out the clockspring. It didn't fix the horn and I'm going to see about the CC, but likely still out as well.