My fuse #7 and the blue and green fused relays in but above the fuses in the fuse box have "no power". Where do they get their power from? Is it the pushbutton unit in the dash or maybe the Klima relay or somewhere else? These elements make the radiator fan run by eventually getting power to it. How could I tap a source and supply power to these parts to basically energize those fans? Thanks.

are you testing with the key ON? I'll look up the diagram when I get home.

The mercedes diagrams are great - and I have printed some on large charts so tracing them is very easy.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Yes, zulfiqar, I am testing with key on....but have tested about every way one could test. Now, today, when I start the car the cabin blower will not blow air and I just put a new resistor and rebuilt the fan motor ..and yes..the 30 amp fuse strip is good.

Some one else mentioned fuse 7 gets power from the ignition switch plus fuse 5 & fuse 6 which have power. They also mentioned fuse B has to be good but I dont think the relays above the fuse box has a B.....they said if these are all good then it is the ignition switch..

The only alternative I see to all this is to put a switch in the dash connected from the battery to the resister behind the drivers light and fuse it of course. I can then turn it on by hand when I need the fans.

The fuses to that point in the slow speed relay should get power from the main battery junction block, its the 3 pole block with studs near the battery and the alternator also connects to it. The high speed one gets it from the interior connector behind the knee panel.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

When you say knee panel, what side you mean....Drivers or passenger....Had a slight miracle this evening...all of a sudden the cabin blowers worked, the A/C came on but still not the Auxilary fan(s)...Auxilary Fans worked fine off the car. Thanks so much for your help.