What is this for?
 

Need some help, cleaning up the wiring on my 69 GTO. In the picture below there's a connector that's not connected to anything, anyone know what it's for? Also. what's the box for that's on the firewall?

I can't say where the connector goes but the box in the picture is the horn relay.

Yes, horn relay.
Re: the plug....Windshield wiper motor? Hard to tell not being able to see around it but the wiper motor is close to that location and there is a similar plug going to it.

I have to "guess" the same, wiper motor. And the other thing [pictured] is the horn relay.

I think you guys are on the wrong side of the firewall in your thinking there. That looks like a tranny in the middle so that would be the AC relay on the firewall. That's a piece of the fiberglass AC housing to the left. That plug is the extension that would run out to the harness that splits to the alternator and the A/C compressor.

Looked again you could be right about other side of firewall... but by the time the harness gets there the alternator wires have already ran to the alternator. Not in front of the car so just going off of memory. But if that is the case the relay would have to be for the A/C system. IMO

http://forums.maxperformanceinc.com/...4&d=1250541240

My car is an A/C car with a conversion kit installed. If you look right behind the passenger hood hinge on the leading edge of the cowl there is a relay (?) mounted and a wire that looks exactly like the one you posted running in to it.

The wire I'm talking about to the alternator is a seperate line with an inline fuse. It's the power take off for the AC relay for the high blower, not the main alternator wiring that runs up the drivers side of the motor from that BAT tap and the voltage regulator. the front harness is a single wire with the fuse that runs from the alternator across the front of the motor. the wire links up to the line going to the compressor. That harness runs back along the passenger side of the motor to the plug on the firewall. If you look close you can see that the wire gauges are different on the plug. The real heavy wire is the alternator feed tap, the other ran to the compressor.

Dennis, you are right..the A/C master relay has that 'trapezoid' shape to it's mounting base. The horn relay does not...and the blower cover is shown in the pic. I did not recognize the tranny and thought the dipstick tube in the foreground was the driver's side inside edge of the cowl lip... :o
You are probably right about the plug too.
David, if you are talking about that device on top of the ps cowl, that's the ambient temperature switch. The plug is similar but doesn't have the 'barbs' on the sides.

A/C Relay, thanks that must be it and it is the passenger side. :)

I think it's power/ground for GPS on export GTO's going to South America NOT equiped with A/C. ?????

Greg, yeah, I learned the hard way YEARS ago when I had no high blower on a 70 tempest I had that had the A/C partially stripped off. I got sick of only having the medium blower on the winter car and tracked down why when I found that plug not connected to anything after tracing through the wiring to find out where the blower power was coming from.

Ok guys you have me thinking. So that connector not being connected. Is that why my blower motor won't work on the high setting?

Well, sounds to me like you just verified that he's right about what the plug is...lol

Should have been more clear, is there a way I can fix it without installing the A/C so the switch on the dash works in the high position and the fan will blow full speed?

yes. run a jumper wire with an in line fuse from the alternator BAT line to that thick gauge wire of your two wire plug hanging there and you'll be good to go!

Just trying to make sure my head is screwed on straight. :) So you're saying if I take a constant +12 lead, attach it to a fuse, say 5 or 10, and then connect it to the thicker of the two wires on that two prong connector, then when I turn the car on and switch the fan to the high position the fan will run at max speed? :)

Yes. but the fuse should be a 20 amp. You could do it without a fuse but I wouldn't take the chance as pulling 12v from the alt tap will give it juice when the key's off. The relay lights up when the ignition is on to give the switch control over the full voltage to the blower motor. Without a fuse to blow, the line could fry if the switch shorts and cause you some bigger troubles like the car burning down.

The reason you've got a fan on the lower speeds is that it's running through the blower resistor for the low and medium settings. The high setting bypasses that and runs the motor at a full 12v via that connector from the alternator.