B3 coupe - automatic to manual climate head conversion

[cgharibo]

Hello everyone,

I have access to a manual climate control ‘95 90. I would like to swap the manual setup and rid of the automatic climate control GM unit.

Is there a write up to enable this? I think the airbox will be a direct swap but I need help with the wiring!

Any write ups on this climate control swap?

Thank you.

[johne]

The GM unit was only used on North America cars, as far as I'm aware there's never been a writeup on here about removing it but it's pretty simple; just use the Bentley workshop manual to show you the how. The wiring changes you can work out from the Bentley wiring diagrams.

[ottawa coupe]

S2 central has wiring diagrams that are representative. It's not overly complicated, the connectors between the system and the rest of the car are identical.

Once you know how to read the diagrams, you're good to go.

[cgharibo]

I removed the B4 manual climate control heater box with three cables attached to transplant to my my B3 CQ. All went fine except the white clip that secures the cable to the bottom of the heater box broke. Any thoughts on how I can re-secure this cable?

Also, can I leave the B3 CQ auto climate control evaporator box, blower fan and its resistor in the car and just transplant the heater box?

Thank you!

[johne]

Almost certainly, yes. In the 90's it was Audi's standard practice to keep the core centre heater unit the same size across their range of cars and alter the fan/evaporator units to match the width of the car and LHD and RHD variants. I see no reason why the same logic wouldn't have applied to B3's.

It was that design practice that enabled me to convert my non climate control RHD '90's car to an electric motor controlled electronic climate control using the core centre heater unit from an A4.

[ottawa coupe]

Not 100% sure about fan resistor. They ARE different but can't recall if the connectors are different too. I believe fan the connection is just a pair of spade connectors? So no big deal there.

[johne]

The fan resistor is matched to the fan motor and there are two fans, one for AC and one without. The non AC unit is smaller, uses less current so needs a different matching resistor. It's possible that only fan motors for AC were ever fitted in North America so there would only be one resistor type.

Whatever resistor pack you use, check the thermal fuse that runs down the side of it as they are often blown and lead you to think you've got a speed control problem when you've just got a blown thermal fuse. Easily replaced for a few cents.

[JariP]

North American models are no different to European models other than some safety items like bumbers, lights and some emissions related parts. GM aircon was used in european and all other market cars up till R12 to R134 change starting from model year 1992.

In fact the rhd UK cars are most different or weird ones compared to any other market area.