Do not understand what you meant by the blower motor resister as I am not familiar with W124 car. There should be no resister in the blower motor circuit as the speed is controlled by solid state electronics. Even if you could then the aux fan will run even when you only call for air, not A/C. I think we are beating a dead horse here as you know what to do to get it right.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.