Mine was eating belts. Turned out that the shop I used to replace the water pump when it went and I was far from home did a poor job. They used sealant on the gaskets which through off the alignment ever so slightly.

Good info here but,

To my knowledge, m52tu engines in E36/7 and E36/8 chassis still used the old fan system. BUT, these were "parts cars":). On mine I have, E30 rear suspension, E36 front suspension, and an engine from an E46:)

Update,

Found the fuse for this. Its hidden under a removable clipped in cover on the top of the glove box fuse box. I had to remove the glove box and then unbolt and lower the fuse box. Under the cover are 3 flat fuses bolted in place (8mm socket nylocs) . The one for the AUX fan was a 60 amp unit.

The 4x red 50 amp fuses on the front face of the fusebox were used for other circuits.

Sound more like the fusible link and not the aux fuse. On my X the aux fuse was one of the 50 amps red fuse.

I have confirmed that the later 2006 E53 diesel (Australian delivery) do not use any of the 4 larger red fuses. The fusebox has some additional fuses on the top of the fusebox that can only be accessed by removing the glove box and unbolting the fusebox unit so it can be lowered down.

The fuse used is a "MIDI" format originally designed by Littel.

Picture of the underside of the fusebox. The red/cyan wire on the right is the one that goes to the Aux fan.
https://dl.dropboxusercontent.com/u/...s/IMG_1419.JPG

The upper side of the fusebox has these fuses. The one for the AUX fan is missing as I was getting a replacement.

https://dl.dropboxusercontent.com/u/...s/IMG_1421.JPG

Picture of the new fuse in place

https://dl.dropboxusercontent.com/u/...s/IMG_1424.JPG

AUX fan now works again. I hit a kangaroo which mushed the front up pretty bad. The fuse must have blown when the AUX fan wiring was mushed up in the mess.

Hi all,
I am having A/C issues in my '04 X5 3.0i E53. I have pulled all 4 red 50amp fuses under glovebox and all are good(NONE of them are labeled as "AUX FAN" whatsoever). I have a free-spinning aux fan(no binding) got continuity on it(+/-), got 12V reading from power harness to fan, fan does not rotate upon start-up or Max A/C activation or at normal op temp, etc.
Unplugged lower rad hose sensor, fan did not go on.
Is there anything else that is affecting the operation of the fan, causing these symptoms? Do the US non-diesel E53's have this MIDI format fuse wired in? I also have ared/cyan wire in my harness. I am kinda stumped.
Would Final Stage Resistor affect aux fan operation, above and beyond when A/C is commanded on......like upon startup test???

Any help or guidance would be appreciated.
Thanks

Steve

Unplug the high pressure AC switch located in the hard AC line next to the compressor. The fan should spin full speed over a few seconds almost like a jet engine taking off. If it does not spin, chance are the fan itself is bad.

Hi all,
Overboost, thanks for the reply. Unplugged high pressure switch and fan roared on, smooth rotation, no bad sounds/smoke!(I did this several times and fan operated every time, but shut down upon reinstalling switch)
So, now I know fan works:thumbup:
Plugged connector back in and compressor sounded like it engaged, but fan slowed to a stop and I assume compressor then shut down again. Is it my switch?
Thanks for help!


Steve

Usually not the switch but at least you have ruled out one of the most common failures (the fan). Time to put some gauges on it and see what it wants.

Today’s AC problem and the fix. AC / air conditioner / Auxiliary Fan

X5 2004 3.0i. 130K miles.

Symptom: AC blowing cool or at ambient temp. 100 degree day during golf trip (La Quinta, CA) – very poor performance. I thought the AC system had a leak. Very sad.

Need Help. I appreciate any recommendations on a brand for a new AC auxiliary fan.

What I did.
Inspected the belt, AC clutch, and 2 service valves, and AC auxiliary fan.

Good. Belt and clutch were operating.
Good. 2 service valves (common leak point) had dust under the caps and no residue (not leaking).

Problem 1 . AC auxiliary fan controller connector was UNPLUGGED! Wire was hanging. I felt very stupid because I was the last one to touch it. Thought that I found the problem, but wanted to get the AC serviced by a pro since it had been over 5 years. It was 60 degrees so no easy way to test the AC operation. But, I’m feeling very lucky.

Indie Mech. $315 (SoCal)
Evacuate and recharge AC frion + add Dye to test for leaks.
No visual issues. Frion level was on the low side of the scale(potential bad sign)

Problem 1 (again). Auxiliary fan NOT WORKING. Failed. Sh*T the Bed . . . . .nuts!
AC performing ice cold while car is moving (Thank the maker!), and coolish while stopped (no air flow due to failed Aux. fan).

Mech. recommended new BMW Aux Fan ($1,000 to replace. $550 parts/ $450 2.5 hours); and return in 1 week to visually inspect for leaks (look for dye with a special light ).

Outcome: I will likely replace the AUX fan myself once I zero in on a non-BMW brand fan that costs less than a new set of golf irons.