Key warning switch/buzzer

I’m in the middle of resurrecting my tilt column after the near fatal fire. It’s a 70 XR7 4 speed. I bought an NOS turn signal switch and it has 9 wires where the crispy/burnt up switch had 10. Is the missing circuit for a key warning switch? If so, is that separate from the turn switch? My schematic shows it to be a black wire and the NOS switch doesn’t have a black wire.

Yes, that black wire is for the key warning relay buzzer. I’m very surprised that a D0 turn signal switch doesn’t have that black wire, as 1970 was the first year for Mustang/Cougars to incorporate that feature.

1 Like

The retaining screw was missing when I took it apart, so I assume it was disabled/removed back in the 70s. Thanks