Another update for anyone following...

I was able to verify the wiring as illustrated in the EWD that brillo provided. I then rigged up an experiment to measure the voltage on the coil side of the relay with without anything on the switched side.

So, with low beams on and fog light switch on, voltage between G/W and B/R was 12 volts when not connected to the relay coil. As soon as you engage the coil side of the relay, voltage drops to less than 1V and relay does not click.

I then repeated the exact same test with a 9V battery. Voltage between G/W and B/R wires was 9V when not connected to the relay coil. When the relay coil is connected, voltage stayed at 9V and relay audibly clicked.

So, this suggests there's a short somewhere in the factory fog light circuit (I think). As the dash fog light switch isn't a lighted switch, I'm assuming this was a kit added by the PO. So, I followed the wires from the switch up to under the steering wheel cover and see that they're tapped into a G/B and R/B wire.

Anyone out there have any thoughts? I'm curious if that switch is wired correctly. If not, I'm not sure how to proceed looking for this short as all fuses appear fine... I hope I'm not overlooking something simple...

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