...On the driver's side...

...Passenger's...

Both buried under the dash as shown, discovered while I was attempting to get the heater blower motor working again (isn't the motor itself btw, now suspecting bad selector lever?)

Anyway, I'm puzzled as to what the above do... I can indeed "push" and "pull" them, and when pushed or pulled they appear to block air flow out of a slot, and when in the middle air can freely exit that slot...

Which seems a bit useless, and as the heater blower motor still doesn't work, it's harder to tell in practice what their function must be, doesn't seem to be in any manuals, I'd love to hear what they do :laugh:

...Also, extra credit...

In this bundle of wires in the passenger footwell on the tunnel, the red and green lead to connectors which have been pulled and taped in that way to the harness... My theories are that they either lead at one point to the cat/floor lights, or is it possible that these are a holdover from the 74MY when they might have been a part of the won't-start-unless-your-seatbelt-is-fastned system?

Thanks!

Those are extra vents for your ac/heater. I always liked mine in my first 77. Wish my 76 had them.

I am not sure what year car you have, but on the 240Z's there is a "hidden" in-line fuse holder for the blower motor. It is up in the wiring harness behind the heater panel.

The previous owner of my car had taken the entire heater panel out and even replaced the fan switch apparently trying to find the problem. I stumbled across the in-line fuse holder when I was re-assembling things, and being naturally curious I opened it up to see what was inside. What I found was a blown fuse... I can't remember now whether it was a 10A, or a 20A. I do think that it shows up on the wiring diagram in the Haynes manual, if you look hard enough. (With a magnifying glass.)

I don't think the 280 had those inline fuses but I am probably wrong.

For your blower motor problems check fuses, then the switch, then the blower motor.

Does your 280 have A/C? This would make it a different switch and a few other things in the blower area that are different from the non-A/C cars.