aux fan problem
 

Hi all
AC has not worked since i have owned the x5.

The aux fan does not spin.
I have unpluged the sensor on the AC pipe but still
no fan spin.
Checked the 50amp fuse and thats ok.
Found there is no 12 volts to the connector to the fan just 3.4v at the thin
signal wire.
I tried by putting 12 volts to the fan plug but nothing.

Thank you all in advance.

very hot dave king

So did you check that continuous voltage from the fuse to fan? That thin wire is PWM signal from DME. You can activate it with diagnostics or PWM signal generator. Direct voltage on PWM wire won't work.

That "Thin" wire provides what is known as a modulated pulse signal to the electronic in the fan. Get a scanner that can read BMW code and do a scan of the X5. A bad fan will show up in the DME module.

Hi
thanks for your reply.
I have read that the fan should
have a permenant 12 volts which
i don't have.
As i said fuse is fine.

thank you.

Dave king

Did you check all of the 50amps fuses? I believe one is a Spare and it doesn't provide power to any circuit.

Hi
i got 14 volts both side of the big green fuses.
even removed the and checked for corrosion.

Thank you.

Did you check the voltage on the 50 A fuse base? Can you give the specs of the vehicle.

Edit: You already answered the first one.

If the aux fan is bad or non functional it will throw a DME error. Check for errors in the DME...

Ok thank's for the reply's.

will fire up inpa later and let you know what i get.

If you really don't have voltage on the thick red/blue wire on the fan connector diagnostics won't give us any more information. If we are talking about pre-facelift built before 9/2003 check the continuity/resistance on that supply wire between fuse F61 and fan connector.

https://www.newtis.info/tisv2/obj/CUGCXF5R

https://www.newtis.info/tisv2/a/en/e...4i-sav/bkWhT11

Hi
its a 2003 3.0d msport.
will check the from fuse to plug.

I do remember when i first got the x5 i had some
problems.
While using inpa i see activate fan.click on it and
it done nothing.

My 50amps fuse was Red.

Do you have a DME error?

Ok
so i checked from fuse box to fan plug and there is a break some where.
run a live to the plug and the fan twitched.
so getting some where.

i need to do a scan now.

thank you all.

dave king

The scan will tell you that the fan is bad because it didn't receive the signal, but it is a false positive if the reason is no power to the fan. The DME will spin the fan at start up and and when the power is removed the fan will continue to spin. A DC motor when spinning becomes a generator when no power is provided. The DC power is the signal to the DME that the fan is good. If you don't have power at the fan connector but have power at the fuse box, you need to check the wiring from the fuse box to the fan.

Double check the fan connector so that wire is not broken or corroded near the connector pin. Then check the connector X10455 on fuse box. If a 6 mm2 wire was cut somewhere else it would likely be shorted to vehicle body and fuse burned.

https://www.newtis.info/tisv2/obj/CTpTBCRH

I'm having the same issue :(
 

Hello, I am having the same issue on my 2005 X5 (3.0D - Australian Right hand drive).

The Aux fan does half a turn when the AC is turned on but then never re-engages. Unplugging the sensor on the A/C HOT line (as it's been suggested on a separate thread here), turned the AC off (can tell by drop in engine revs and that 'AC was just turned off but air still blowing' smell in the car), it did not make the AUX fan go full speed.

I have also tried to disconnect a lower coolant sensor (which did nothing to affect the AC)

All of the above was done when car was at proper running temp.

Daveking, see my thread below:


https://xoutpost.com/bmw-sav-forums/...continues.html


I think I had the exact same problem as you and I think Fuse F61 may not be the correct fuse. I found that the wiring diagrams at newtis and my bentley manual were both wrong.