A/C harness install

[Hook'em]

I bought and installed a new American Autoworks a/c harness yesterday. I worked backwards removing the old and installing the new, to make sure everything was correct. All wires and plugs accounted for, and connected. My issue arose once I got to the fuse box. The original harness had one connector which plugged into the cig terminal. The replacement harness has two - one orange and one gray.

I believe the orange goes to the cig. Just not sure about the gray. Any ideas?

[Hook'em]

Attempting to attach a photo of the end that plugs into the fuse box.

[Hook'em]

Pretty sure that the large orange wire plugs into the cig spot and the smaller gray wire plugs into the panel light spot.

Everything is plugged in, but nothing happens when engage the switch. The cigarette lighter is plugged in with the orange wire and is working. Although brand new, I'm wondering if the switch is bad.

[clay68c10]

Yes, gray is for the illumination.
Your switch may be bad since none of the speeds work.

[clay68c10]

Did you connect the brown wire for the switch? I recall it ties into the main harness near the ignition switch.
I remember it being brown, but might be wrong. My diagram isn't here to verify.

[MARKDTN]

On high speed you should get battery voltage to the fan motor. It goes through the relay and bypasses the resistor. If not, check to see if you have battery voltage to the fan relay orange wire. The main switch and the relay can have issues. Also make sure you actually have a ground to the blower motor.

[PbFut]

Confirm what is not working. Low/Med Fan, High Fan, Compressor clutch, Right side illumination.
I think the left side bulb is common for heat and AC so it connects in the main interior harness. Pretty sure but not 100%, the right bulb is for AC only panels and is powered in the add-on AC harness. Gray wire is for the right bulb and plugs into the gauge lights pin on the fuse block so you get dimmable power and the bulb behaves the same as the rest of the dash. The orange wire is the primary source for the high speed blower fan and compressor clutch. The switch selects a path through the resistor for low and med fan speed. High speed switch setting triggers the relay on the side of the air box in passenger foot well and sends a full 12v to the fan via the relay. That relay must be grounded. The push button switch with two leads on the back side of the air box is the switch for the compressor. It often gets knocked off when messing with the air box installation. The middle lever on the control panel opens the air mix/blend door in the air box directing air to the heater core or air evaporator. Mid position will blend both air paths to adjust temps. You will see a line on the panel. The line represents the approximate position of the lever that the cable will trigger the compressor switch. The lever moved more left compressor remains on and air door isolates AC evaporator. Move the middle lever right and the door switches to heater core path and turns off the compressor switch. The upper lever only adjusts vents via cable and vacuum to the heater hose and outside vent door cans. It does not trigger anything electrical though it seems so. For those using EFI systems, the button switch is the perfect place to tap for AC trigger signal to the ECU and not have an extra wire in the engine bay or off the compressor.

[Hook'em]

Originally Posted by clay68c10

Did you connect the brown wire for the switch?

Apparently that little wire does have a purpose. It was tucked back under the dash and I though it must go to the radio or something. Thanks for pointing it out.

I broke one of the connectors on the switch trying to get the wires back off. Luckily, I keep replacement switches around. Added to brown wire and added a new 25a fuse to the panel and its blowing and going.

Thanks, as always, for the helpful responses.

[clay68c10]

Good to hear and thanks for the update. This may be helpful for someone in the future.