Chrysler Repair: 1990 Chrysler NYer blower motor resistor, blower motor resistor, chrysler new yorker

Question
I am trying to work on my grandpa's 1990 Chrysler New Yorker Salon.  The blower motor doesn't work.  I have voltage to the motor and shorted it to ground and the motor spins.  I assume the problem is the blower motor resistor.  I don't know where it is or how to test.  What are your thoughts about this?  Please explain the location of the resistor or give other ideas of what else could be wrong.  Thanks.  Any information will be greatly appreciated.  Brian

Answer
Hi Brian,
The resistor "block" is described in the wiring diagrams as being in the right side of the cowl plenum. What this means is that the resistors of the block are placed in the air stream that brings outside air to the heater, located at the base of the windshield, inside the concealed duct on the passenger side.  But I believe that the block is inserted into that duct from the cabin side of the firewall. It is likely located above and behind the glove box. So I believe that you will want to remove the glove box to get to it. There are screws around the glove box door opening that you remove, and you may need to remove the pad on the lower edge of the right side dash panel in order for the box to drop down. Then when you look through the opening you should see it as a rectangular object with a 5-pin plug  that is held by 2 screws. Pull the plug, remove the screws, and the block will come out into the cabin area and you will then see the resistors. If you trace the black/tan wire from the blower motor, that too should lead you to the resistor block. There are several resistors, the one that would stop the motor entirely from working is between the black/tan wire and the gray wire pins of the block, if it burned out.
It could be that the switch for the fan is not working if it is not grounding each of the positions to a black ground wire that is tied to a ground point on the right side cowl, behind the trim panel. But chances are it is that single resistor has blown. You could verify that pins 3,4,5,6, are connected to pin 7 of the control panel when the fan is set to low, medium 1, medium 2, and high speed positions, respectively to check that switch failure possibility.
Good luck with the project.
Roland