E46 Electric Fan issue

evnmopwr

Well-known member
Ok so i acquired a 2001 E46 325i touring (Manual)
It has the Electric Fan ( Between Radiator and Engine ONLY ) no aux fan and viscus like the Auto models.

https://ibb.co/mhbosk

I have Searched But non specific to mine...

It was knocked in front and I have repaired it..

First test driver after Accident repair:
* Car drove fine and Fan was not on
* At operating Temp, the Fan kicks on and made this Loud, metal on metal Noise.
* It disengaged ( Shut off ) and carried on with test drive.
*While siting and reading codes for a Missfire, noted the Temp gauge broke the halfway mark
* Fan refused to come on at all

I removed the Fan and it was pretty difficult to spin up...
So i figured it got hurt in the accident so i got a replacement part from a Breaker, it came off a 318i touring with about 180k on the clocks..
Fan looked near new condition...

Installed the new fan

Second test drive after Fan replacement:
* Car starts and after about a Minute or so, The fan kicks on
* this happens even on COLD START
* Fan stays on and spins at High speed all the time the cars on
* Fan switchs off when i turn the engine off
* Fan Stays off

Troubleshooting:
* Temperature stays at the halfway mark
* No errors Detected on Delphi
* Checked and Replaced the 50A Fuse on Fuse box
* Tested continuity on the Small Green wire to the Fan plug
* Removed and Refitted the Fan
* Checked Coolant levels
* Checked for water leaks
* Bled coolant system again

There are no Relays to check on these fan setups as the Silver control box between the Fan and the Plug is what communicates to the DME ... NO RELAY!! :thumbdo:

Now, the Breaker is adamant that the fan is 100% ok and stated that the Car he removed the part from, (i was standing there when he removed it), blue its head gasket due to a Fault Thermostat and not the Fan not working.

With the Fan spinning, Clearly its "Working" but not as it should

Question:

* Is this Fan a DUD?????!!!!!
* Could a Faulty Coolant Temp Sensor cause this? ( I did not replace this during
Accident Repair )

There are still no codes at all...
I was told that should this fan burn out, It could start a Fire...
So a bit worried about this and the Breaker is not playing ball

Any info would help.
 

Gizmo

Banned
Was the temp sensor on the lower radiator hose damaged in the accident?
Sounds like the ecu is going into a default state not knowing the temp and turns on the fan.


I would try a friend's e46 electric fan and see if you get the same result. It's rather quick and easy to swap out anyway.
 

evnmopwr

Well-known member
Gizmo@GARAGE46 said:
Was the temp sensor on the lower radiator hose damaged in the accident?
Sounds like the ecu is going into a default state not knowing the temp and turns on the fan.


I would try a friend's e46 electric fan and see if you get the same result. It's rather quick and easy to swap out anyway.



The sensor has Def seen better days, Orange Soot all over the tip, A bit of oversight on this During the rebuild of the car on my part


KPM_330 said:
Take your car to your nearest Silverton Radiator centre and have them test the cooling system for you.

http://www.silvertonradiators.co.za/index.php/dealer-locator

None in cpt??
 

Blue Shirt

Well-known member
Replace the temp sensor in the lower radiator hose, it sole function is to tell the ecu to switch the fan on/off at the correct temps and make sure the wiring to it is not damaged.

Also look for the ground connection on the fan wiring harnass, (the section that supplies the power/ground to the large connector) and make sure it is securely bolted to the chassis leg. I once had a situation where this ground connection was not properly fastened after an aircon repair.
 
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