What plugs into this?!

[SmokingRocks]

So I finished putting my dash back in last night and then I saw this one plug behind the stereo... I can't find what plugs into it! I'm at a loss.

I trace it down to the bottom of the air box, is this a sensor for the auto climate control? This 93' is a near poverty pack so don't have auto climate control.

I looked back at the old harness and can't find any plug in the area that matches it.

 

[mechanist]

Also curious. I thought it was the alternative harness for the speakers.

 

[Rifleman]

Just an thought, but i think it's a plug for optional equipment that didn't come on your truck.

 

[jbatx]

I think that might be the "pwr" button plug that changes the shift points for more "pwr". Do you have one?

 

[SmokingRocks]

nope that's not it. It's certainly HVAC controls related.

 

[Clint0511]

It's for the thermistor. Should plug in above the ac module by the passenger airbag.