E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   E46Fanatics > E46 BMW > General E46 Forum

General E46 Forum
This is the place to get answers, opinions and everything you need related to your E46 (sedan, coupe, convertible and wagon) BMW!

Reply
 
Thread Tools Search this Thread Rating: Thread Rating: 2 votes, 5.00 average. Display Modes
Old 10-12-2013, 01:21 PM   #1
RazrE46
Registered User
 
Join Date: Oct 2013
Location: Holland
Posts: 8
My Ride: E46 316 1.9
Exclamation Engine fan does not engage

Problem description:
The fan (engine cooling) does NOT engage when it should. Actually the fan never engages even when the temperature rises towards the red zone. I already had an overheated car twice after I got stuck in a traffic jam.

What did I do already?
A couple of parts have been replaced. A complete new fan together with the control module (I think you cannot even buy it separately actually). Also a new temperature sensor is in place (the coolant sensor in the lower radiator hose). Last but not least recently (two weeks ago) also a new thermostat is placed.

At first we thought the fan would not go on simply because it might be broken. Well, it turns out it is not since the new fan still does not engage when the coolant temperature gets above 105 degrees Celsius. The fan does have the required voltage on provided, and the signal wire (PWM) also seems to be alright. The t-stat opens when it should, and afterwards the lower hose noticeable gets warmer, also the sensor value indicates a higher temp. when this happens - all good.

Since yesterday I do have some diagnosis capabilities (INPA and DIS) and I ran the 'electric fan' test a couple of times. Directly after I start the test the fan engages to full speed for ~30 seconds. So for that part everything seems OK. There is an error saved in the DME module though, it reads:

"(108) 6C Activation, electrical fan". Furthermore it says "Open circuit" and that the error is currently available.

The error returns directly after I clear the error memory - this must be related. I also check all the fuses and visually inspected the cables running from the fan / temp. sensor back to the front of the car.

What do we know:
  • Testing the fan with diagnosis software works.
  • Values from both the temp sensors in DIS look OK when running the car.
  • Fan, coolant temp. sensor and t-stat is all new.
  • Error 108 keeps returning in DME.
  • Fuses are all OK.

I do not know where to look anymore. Is there anything else I could try/test to isolate the problem? Could it be the DME that is failing (I hope not)?

edit: The car is a E46 - 316 1.9 (2001-01) M43 engine.
edit2: It's a manual transmission. This means it has not pusher fan, only one electrical (radiator) fan.

Last edited by RazrE46; 10-12-2013 at 02:19 PM.
RazrE46 is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.
Old 10-12-2013, 01:31 PM   #2
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
Did you check the connectors on the harness to the fan, as in the contacts? Maybe its not able to read a signal from the fan that lets the computer know when its been engaged and what rpm its running at?

Id clean the contacts, and possibly check on crimping the pins slightly to start with. Also, your aux fan may be the actual culprit from what Ive read in the past.
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 01:48 PM   #3
RazrE46
Registered User
 
Join Date: Oct 2013
Location: Holland
Posts: 8
My Ride: E46 316 1.9
Quote:
Originally Posted by JohnnyJTown View Post
Did you check the connectors on the harness to the fan, as in the contacts? Maybe its not able to read a signal from the fan that lets the computer know when its been engaged and what rpm its running at?

Id clean the contacts, and possibly check on crimping the pins slightly to start with. Also, your aux fan may be the actual culprit from what Ive read in the past.
Yes I did check a lot of connectors and cleaned them as well (including the ones related to the fan). I do not know if the DME is actually aware of the fan running or not. I do know that the signal wire carries an PWM signal that instructs the fan's control unit to engage and at which speed. This signal cable works I guess because the fan test I ran via DIS makes the fan engage at full speed.
RazrE46 is offline   Reply With Quote
Old 10-12-2013, 02:04 PM   #4
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
Check any relays associated with both the pusher fan and the cooling fan. Ive never had this problem before so I personally cant give any exact answers. Maybe someone with similar experience in the past will come along and help.

I had a similar situation with my oldsmobile, faulty relay would work sometimes, more often not.

To me it can only be so many things. Whatever controller board sends the pulse width modulation signal, relays, fuses, the fan itself, temp sensor, aux fan (pusher fan) being busted causing a domino effect possibly.... etc

My guess is still the connectors, I would check the pusher fan connectors also, if you havent already.

Hope you get it sorted.
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 02:06 PM   #5
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
Quote:
Originally Posted by RazrE46 View Post
I do not know if the DME is actually aware of the fan running or not.
I think that may be why you are getting open circuit errors, something may not be getting the signal it is expecting.

If it doesnt end up being something simple or a sensor, it "might" be whatever controller board hosts the transistors/mosfets used for the PWM?
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 02:18 PM   #6
RazrE46
Registered User
 
Join Date: Oct 2013
Location: Holland
Posts: 8
My Ride: E46 316 1.9
Quote:
Originally Posted by JohnnyJTown View Post
Check any relays associated with both the pusher fan and the cooling fan. Ive never had this problem before so I personally cant give any exact answers. Maybe someone with similar experience in the past will come along and help.

I had a similar situation with my oldsmobile, faulty relay would work sometimes, more often not.

To me it can only be so many things. Whatever controller board sends the pulse width modulation signal, relays, fuses, the fan itself, temp sensor, aux fan (pusher fan) being busted causing a domino effect possibly.... etc

My guess is still the connectors, I would check the pusher fan connectors also, if you havent already.

Hope you get it sorted.
I forgot to mention that I have a manual transmission, and those do only have a single (radiator) fan. There is no pusher fan on those models. Also there is not any relay as far as I know. The fuses are all checked and good. The fan and temp sensor both are replace and the problem still persist. I agree that perhaps the board which controls the PWM signal is faulty. That must be the DME module.

Quote:
Originally Posted by JohnnyJTown View Post
I think that may be why you are getting open circuit errors, something may not be getting the signal it is expecting.

If it doesnt end up being something simple or a sensor, it "might" be whatever controller board hosts the transistors/mosfets used for the PWM?
I think so too. That would be the DME module controlling the PWM signal. One of the main modules (and most expensive). But the fact that when I connect my car to the diagnosis software (DIS) and run the 'electric fan test' with success makes me doubt that there is something wrong with the PWM signal. I do not have a oscilloscope but the voltage does change on the signal wire when running the test (the fan also spins at full speed). Thanks for you input, appreciate it.

Last edited by RazrE46; 10-12-2013 at 02:19 PM.
RazrE46 is offline   Reply With Quote
Old 10-12-2013, 02:37 PM   #7
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
Quote:
Originally Posted by RazrE46 View Post
I forgot to mention that I have a manual transmission, and those do only have a single (radiator) fan. There is no pusher fan on those models. Also there is not any relay as far as I know. The fuses are all checked and good. The fan and temp sensor both are replace and the problem still persist. I agree that perhaps the board which controls the PWM signal is faulty. That must be the DME module.



I think so too. That would be the DME module controlling the PWM signal. One of the main modules (and most expensive). But the fact that when I connect my car to the diagnosis software (DIS) and run the 'electric fan test' with success makes me doubt that there is something wrong with the PWM signal. I do not have a oscilloscope but the voltage does change on the signal wire when running the test (the fan also spins at full speed). Thanks for you input, appreciate it.
Ahhh Thats right, manual or automatic with electric fan mod = no pusher. My bad.

As far as the PWM board (like I said, I dont know anything about the fan system as I have never ran into any problems in the past) My thought was not so much the pwm signal going out, but the signal coming back from the fan to that board, if thats how it works. (I should do some searching to see exactly how this sytem works.)

I see that the fan works at full speed when running the standard test, but What kind of test did you run to get the voltage to vary? I would think if you measured the pwm working (voltage varying), with a multimeter, it would also cause the fan to work at varying speeds for that same test.

Lastly, quick question before I do some schematic searching. did you check for continuity of each wire in relation to the connector, to make sure there isnt some sort of wire break before it hits the actual connector?

From what I can see, the fan def sends rpm signal back out, to somewhere. If you have a wire break, and its no good in the connector, it may be causing problems.
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 02:54 PM   #8
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
The new fan cam with a final stage resistor right?
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 03:12 PM   #9
NumbaOneNewb
Registered User
 
Join Date: Jul 2012
Location: Portland, OR
Posts: 3,150
My Ride: 2003 330CI Silver
I took the liberty to look at some schematics for you. Have you checked fuse f37 with the 50A fuse? That seems to be part the electric fan system.
__________________
Portland Metro: ECU updates, Euro tune, euro corner delete, air bag light, DSC light, cluster and any led color change, soldering work, transponders for keys, and all custom work related to computer or electronics.DIY AK90 A walk through on coding your mcu and transponders EWS3 How to make your own key (ak90 review)
NumbaOneNewb is offline   Reply With Quote
Old 10-12-2013, 03:21 PM   #10
NumbaOneNewb
Registered User
 
Join Date: Jul 2012
Location: Portland, OR
Posts: 3,150
My Ride: 2003 330CI Silver
another question, i'm assuming that when you say electric fan mod, this car originally came with the mechanical fan correct? or no? if it did, there also wasn't any other fan like say the ac fan also correct? also take a look at this screen shot.
Attached Thumbnails
Click image for larger version

Name:	fan.jpg
Views:	55
Size:	104.5 KB
ID:	530574  
__________________
Portland Metro: ECU updates, Euro tune, euro corner delete, air bag light, DSC light, cluster and any led color change, soldering work, transponders for keys, and all custom work related to computer or electronics.DIY AK90 A walk through on coding your mcu and transponders EWS3 How to make your own key (ak90 review)
NumbaOneNewb is offline   Reply With Quote
Old 10-12-2013, 03:22 PM   #11
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
From what I can tell, the DME just completes the circuit using ground, not sure why that would be an extremely expensive part. Didnt see anything for a signal from the fan, back to the DME.

On a side note, after doing some reading, another BMW owner had the same situation and resolved it by bleeding the cooling system. Seems there was an air pocket or something that caused his fan not to turn on.

Another owner solved by switching the temp sensor, and another resolved with a new fan lol. But since you already replaced those...

Weird. Seems like a pretty simple system, you would think the problem would be extremely apparent.
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 03:24 PM   #12
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
Quote:
Originally Posted by NumbaOneNewb View Post
another question, i'm assuming that when you say electric fan mod, this car originally came with the mechanical fan correct? or no? if it did, there also wasn't any other fan like say the ac fan also correct? also take a look at this screen shot.
That screenshot tells me that if you unplug the temp sensor, the fan should kick on and stay on as a type of protection feature.
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 03:29 PM   #13
NumbaOneNewb
Registered User
 
Join Date: Jul 2012
Location: Portland, OR
Posts: 3,150
My Ride: 2003 330CI Silver
perhaps that should be what he should try to make sure the signal is returning back to the dme. the diagram states that the dme has 1 wire that leads to temp sensor and the 2nd wire from temp sensor goes right back to dme. from there, the dme sends another wire out to the electrican fan, which combined with a wire leading from fuse 37 for power and i'm sure at least another wire for ground should complete its circuit.
__________________
Portland Metro: ECU updates, Euro tune, euro corner delete, air bag light, DSC light, cluster and any led color change, soldering work, transponders for keys, and all custom work related to computer or electronics.DIY AK90 A walk through on coding your mcu and transponders EWS3 How to make your own key (ak90 review)
NumbaOneNewb is offline   Reply With Quote
Old 10-12-2013, 03:32 PM   #14
NumbaOneNewb
Registered User
 
Join Date: Jul 2012
Location: Portland, OR
Posts: 3,150
My Ride: 2003 330CI Silver
I'm sure wondering whether the car originally came with an electric fan or not. I've noticed that e46s sold outside the US tend to lack prewired connections for future additions, an example being the alarm security system. if you didn't ask for it when it was 1st bought, the wires for them aren't there. this could be one of those situations.
__________________
Portland Metro: ECU updates, Euro tune, euro corner delete, air bag light, DSC light, cluster and any led color change, soldering work, transponders for keys, and all custom work related to computer or electronics.DIY AK90 A walk through on coding your mcu and transponders EWS3 How to make your own key (ak90 review)
NumbaOneNewb is offline   Reply With Quote
Old 10-12-2013, 03:32 PM   #15
BMW-North
Registered User
 
Join Date: Feb 2008
Location: SC or ON
Posts: 418
My Ride: 01ci,03i,03xi,04xi
Check for this:

1. Does the fan spin (briefly) when the key goes to position 2? It is part of the self check? It will then stop till it gets another signal (usually temp or ac related)

2. Does the fan spin when the engine is running and you turn on the ac compressor (on the manual trans - this activates the fan via the aux fan relay (AFR) module)

If both are no - it would appear a bad fan control module but you said you changed that?

In a worst case scenario you can use the old fan - bypass the fan control module and just send a constant 12v to the electric fan - this will stop overheating and let you drive the car till you can diagnose the real cause.

If the AFR is good then I would suspect the ECM may not be sending the signal - it is difficult to determine but can be done.

3. Check these prior threads:

http://www.e46fanatics.com/forum/sho...d.php?t=851978

http://forum.e46fanatics.com/showthread.php?p=13516820

Last edited by BMW-North; 10-12-2013 at 03:46 PM.
BMW-North is offline   Reply With Quote
Old 10-12-2013, 03:32 PM   #16
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
Quote:
Originally Posted by NumbaOneNewb View Post
I'm sure wondering whether the car originally came with an electric fan or not. I've noticed that e46s sold outside the US tend to lack prewired connections for future additions, an example being the alarm security system. if you didn't ask for it when it was 1st bought, the wires for them aren't there. this could be one of those situations.
Its a manual, they have electric fans from the get go.
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 03:36 PM   #17
NumbaOneNewb
Registered User
 
Join Date: Jul 2012
Location: Portland, OR
Posts: 3,150
My Ride: 2003 330CI Silver
not necessarily. perhaps he may have been right on time to hop on the bandwagon for electric fans on manuals but they didn't always come that way.
__________________
Portland Metro: ECU updates, Euro tune, euro corner delete, air bag light, DSC light, cluster and any led color change, soldering work, transponders for keys, and all custom work related to computer or electronics.DIY AK90 A walk through on coding your mcu and transponders EWS3 How to make your own key (ak90 review)

Last edited by NumbaOneNewb; 10-12-2013 at 03:36 PM.
NumbaOneNewb is offline   Reply With Quote
Old 10-12-2013, 03:38 PM   #18
JohnnyJTown
Registered User
 
Join Date: Jul 2009
Location: Chicago
Posts: 124
My Ride: 99 323i
Quote:
Originally Posted by BMW-North View Post
If both are no - it would appear a bad fan control module but you said you changed that?
Thats whats bad about some situations, you can replace the part, only to find out later that it was defective. I hate those situations.

I think its air in the cooling system or a break in the wiring somewhere. Those tests mentioned above (Removing the temp sensor connector to see if the fan kicks on etc) are a good place to start, along with what BMW-North mentioned also.
JohnnyJTown is offline   Reply With Quote
Old 10-12-2013, 03:50 PM   #19
RazrE46
Registered User
 
Join Date: Oct 2013
Location: Holland
Posts: 8
My Ride: E46 316 1.9
Quote:
Originally Posted by JohnnyJTown View Post
Ahhh Thats right, manual or automatic with electric fan mod = no pusher. My bad.

As far as the PWM board (like I said, I dont know anything about the fan system as I have never ran into any problems in the past) My thought was not so much the pwm signal going out, but the signal coming back from the fan to that board, if thats how it works. (I should do some searching to see exactly how this sytem works.)

I see that the fan works at full speed when running the standard test, but What kind of test did you run to get the voltage to vary? I would think if you measured the pwm working (voltage varying), with a multimeter, it would also cause the fan to work at varying speeds for that same test.

Lastly, quick question before I do some schematic searching. did you check for continuity of each wire in relation to the connector, to make sure there isnt some sort of wire break before it hits the actual connector?

From what I can see, the fan def sends rpm signal back out, to somewhere. If you have a wire break, and its no good in the connector, it may be causing problems.
There is only a single test I can perform with DIS software. It runs the fan at full speed for 30 sec. When the fan isn't engaged, the signal wire reads around 4v I believe. This drops to 0.4 or something when the test is being run. I cannot read the PWM values due to the lack of equipment. Continuity seems all good on the wires/connectors.

Quote:
Originally Posted by JohnnyJTown View Post
The new fan cam with a final stage resistor right?
Don't think so, is this resistor not related to the heater blower in the car only?

Quote:
Originally Posted by NumbaOneNewb View Post
I took the liberty to look at some schematics for you. Have you checked fuse f37 with the 50A fuse? That seems to be part the electric fan system.
Thanks for the effort, but yes the fuse is all good. Also the fact that I measure 12v at the fan + that the fan test works makes me think that it has the required juice.

Quote:
Originally Posted by NumbaOneNewb View Post
another question, i'm assuming that when you say electric fan mod, this car originally came with the mechanical fan correct? or no? if it did, there also wasn't any other fan like say the ac fan also correct? also take a look at this screen shot.
It did had the electrical fan already, this is factory spec. There is no AC fan, this engine cooling fan should also go on when you turn on the AC.

Quote:
Originally Posted by JohnnyJTown View Post
That screenshot tells me that if you unplug the temp sensor, the fan should kick on and stay on as a type of protection feature.
I believe I tried that - will try it again tomorrow. Anyhow if I remember correctly, the fan didn't engage when the sensor was unplugged. The only thing that happend was another fault code being stored in the DME (which is a good thing of course).

Quote:
Originally Posted by NumbaOneNewb View Post
I'm sure wondering whether the car originally came with an electric fan or not. I've noticed that e46s sold outside the US tend to lack prewired connections for future additions, an example being the alarm security system. if you didn't ask for it when it was 1st bought, the wires for them aren't there. this could be one of those situations.
Yup, it came with the electrical fan. http://realoem.com/bmw/showparts.do?...39&hg=17&fg=05

Quote:
Originally Posted by BMW-North View Post
Check for this:

1. Does the fan spin (briefly) when the key goes to position 2? It is part of the self check? It will then stop till it gets another signal (usually temp or ac related)

2. Does the fan spin when the engine is running and you turn on the ac compressor (on the manual trans - this activates the fan via the aux fan relay (AFR) module)

If both are no - it would appear a bad fan control module but you said you changed that?

In a worst case scenario you can use the old fan - bypass the fan control module and just send a constant 12v to the electric fan - this will stop overheating and let you drive the car till you can diagnose the real cause.

If the AFR is good then I would suspect the DME may not be sending the signal - it is difficult to determine but can be done.

3. Check these prior threads:

http://www.e46fanatics.com/forum/sho...d.php?t=851978

http://forum.e46fanatics.com/showthread.php?p=13516820
1. Will check this tomorrow, good thought.

2. I am not sure about this one. When the engine runs and I put on the AC the fan spins up (like 20%). After 10 seconds it slows down and it comes to a complete stop. 10 seconds later the fan spins up, 10 seconds later spins down etc. etc. This does not seem right.

3. Going to read them.

Thank you all for you input guys, much appreciated!

Last edited by RazrE46; 10-12-2013 at 03:55 PM.
RazrE46 is offline   Reply With Quote
Old 10-12-2013, 03:55 PM   #20
BMW-North
Registered User
 
Join Date: Feb 2008
Location: SC or ON
Posts: 418
My Ride: 01ci,03i,03xi,04xi
One other thread that will help you tomorrow:

http://forum.e46fanatics.com/showthread.php?t=766256

BTW - if you can activate the fan via DIS then your wiring is fine.
BMW-North is offline   Reply With Quote
Reply

Tags
dme, fan, overheating

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Censor is ON





All times are GMT -5. The time now is 12:19 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
(c) 1999 - 2011 performanceIX Inc - privacy policy - terms of use