Greetings XF guys! I'm new to the XF and this forum. My GF traded her son for a 2006 XF. He's off to coach a rural school and needed a bigger car. I've had some surprises reading about this 80% Mercedes vehicle. (Like why the need for two plugs per cylinder? I understand 2 valves...but not plugs! :-) )

Anyway, I've got the spoiler and the vert working for the 1st time in 4 years of ownership. Now, I'm looking at the cause of the coolant light. After reading on this forum, I looked for blown fuses and didn't find one. I turned on the A/C and the fan doesn't run. I unplugged the fan and jumped it directly. The fan works. The 50 amp fusible link for the fan appears in tact. So... It would seem the FCM must be bad -- though that's one of the few items already replaced by her son, the PO. So...I thought I'd break the ice and jump in to make sure I'm not skipping anything before looking for another FCM. (I guess I should verify there's a 12V feed into the connector for the FCM.

Oh yeah...What might cause multiple FCM failures -- if that's our problem?

I read the FCM is PW modulated to vary speeds. I see four heavy guage 12V (dual in/out) cables and two small voltage wires. I assume the later provides input for PW modulation of the output voltage. Since the car runs pretty well w/o the fan (except when calling for A/C operation), I wonder if that stupid thing couldn't be replaced with a simple 2-sp fan controller? Of course, IDK what type of signal is coming into the controller yet. I didn't measure it with my VO meter -- but maybe it's a digital feed?

Please let me know what to do next before looking online for ANOTHER FCM.

Thanks in advance for your help. Happy 4th and nice to chat with you guys! :-)

Gregg

(FWIW...My car is a fully customized 89 Vette with a 383 stroker pulling 440 ft/lbs of torque. Basically, I upgraded it to run like a Z. I've yet to delve into the luxury foreign car world being a Detroit fan. It will be interesting to see how this "Mercedes" thing pans out. I'm a bit concerned about cost of maintenance, but hey...the XF is a really nice looking sports car! )

Thumbs up!
:-)