Cooling Fan Hookup

[joshr65]

Hello All,

I have purchased a cooling fan for my 85 VW cab. The fan has 3 male connectors and my harness has 2 female. The original fan has 2 also. The place I bought it from said it is diff because I have AC. I have removed the entire AC system from the car. They told me there is an adapter I need to get. The part is called a Fan Motor Connector Housing
1H0 906 233

I am hoping I can just wire direct w/o need for the other part. ANy ideas???

Thanks,

Josh

[gull]

Does your 2-pin connector physically mate with the 3-pin connector on the fan? I think some of them were the same housing, just with a pin missing. If it mates up I think it should run on high speed.

[joshr65]

It mates up on either the left 2 pins or the right two pins.....

[kamzcab86]

You'll need the adapter, or just make jumper wires from the harness to the fan motor.

Up to '87, the cars had single-speed fans. The motor you have is for a two-speed. A/C cars have two-stage fans; when the A/C is cranked on, the fan is turned on as well. My own '86 has A/C and a single-speed fan with just two connectors (all original).

[joshr65]

Thanks for the replies. The fan only comes when I have it connected to the left 2 male connectors on the fan. Which seems to be hide speed. It turns on when the temp gets past the little temp lite and off with the car so I think it is fine. Interesting side note. I have noticed my car idles low and a little rough around 900 rpm. When the temp selector is moved to defrost, bi-level, or AC setting the idle smooths out and rises to about 1000. When on Heat or Vent it lowers and gets rougher. What could cause this? I have ripped out the AC system out of the car. Maybe I need to remove the ac relay and just raise the idle a little with the idle screw?

Thanks!

[gull]

There's an idle air bypass solenoid on the passenger side shock tower that boosts the idle when the A/C is on. Defrost mode also turns on the A/C, so that's what you're seeing. Actually, there are two solenoids there, one boosts the idle when the A/C is on, the other boosts the idle when it gets too low.

It sounds like your base idle may be a little low. The spec is probably on the yellow emissions data sticker under the hood, but IIRC you squeeze the idle air bypass hose closed and then adjust the idle to something like 850 rpm with the engine warmed up. (That's from memory -- find the real number, don't trust mine.) The dash tach isn't really accurate enough for this -- you should use a tach/dwell meter -- but on my car the correct base idle corresponded to roughly one needle width below the 1,000 RPM mark.