Question on electric fan in 300TE
 

My electric fan works fine at 12 Volts and the car does not overheat. However, it does not work with the A/C on. I measured the voltage at the fan with the A/C on and is like 7.2 volts an dthe high pressure side is over 300 psi. The high pressure switch does open when I check with the meter.
Also, all the relays work OK.
Can someone tell me if the fan will run with 7 volts?
I assume that is why there is a resistor that reduces the voltage for the fan, so it runs slower with the A/C on whenever the freon pressure goes over 20 bar.
Or is this fan worn out??
Please advise
my e-mail is bshah@satx.rr.com
Thanks
Barry