Question about the replacement of the cabin heat/air fan and the regulator. I just followed the directions on the DIY link for the removal of the fan and it was pretty straight forward. My fan is farily free spinning (for a 1990e) so I'm wondering if its the regulator as mentioned in the DIY link. Can I put 12 volts right to the motor without damaging it? Also would like to know what the device is on top of the firewall above the master cylinder that the regulator connects to. But if I read the post right I should be able to tell if its the regulator by just disconnecting the wires at the point above the Master cylinder and electricallly starting the fan...wish I had read that first...sounds like the regulator is a real bummer to get at.

Just ground the blu wire at the motor..that will by-pass the regulator and get full fan.

Thanks Artur. Are you saying to leave the red wire connected to the fan, pull off the blue wire from the fan and actually ground the wire itself, or ground the motor terminal that the lead was on? Also can 12v be connected directly to the red lead for a test too? Also what exactly does the regulator do? I saw The picture in the "parts" section of this site and it looks like it is some sort of temp sensor device. Thanks

Re-read my test.
The red wire is always HOT w/key ON..
The REG simply grounds the motor [ called a SWITCHED ground] using the blu wire.

SO, knowing that, if you simply ground the blu wire from the motor , you have by-passed the regulator/control circuit.
Grounding the blu wire coming out of the motor is the same as if you took the motor out and hooked it up to a battery DIRECT...but why do that if you can do it by simply grounding the blu wire ???
My post didn't go into the WHY , it is just the first of a sequence of TEST.

The first one being . "Ground the Blu wire"

If the motor runs, you have a problem in the control side of the circuit, most likely the reg.
If it does not run, you check that you have 12v at the red ..If you do , you have a bad motor..if No, then you have a bad strip fuse.

Got ya. Thanks for clearing that up for me.