AUX fan woes

[oldskewel]

If you want a software system to do a bunch of stuff, well that's what you're working towards here.

But if you think your fan is bad, and just want to do a more careful test before buying a new one, you don't need anything beyond a voltmeter (true RMS probably required).

There are multiple ways to trigger the fan to come on, and if the rest of your car (ECU, AC, ...) is working fine, they should all work. The simplest (to me) seems to be the one shown in post #24 by @Overboost. Turn AC on, pull that connector off, and the fan should be commanded to run at full speed.

Then you measure voltage on the control wire going to the fan, and see if it behaves like I describe in post #28.

If you see power and ground on the two fat wires in that connector, and the control wire voltage is measured as it should be ... and the fan does not spin ... it's a pretty easy diagnosis. Maybe not 100% certain, but watching the control voltage change as it should will confirm the control signal is not majorly wrong. Definitely easy enough to do before just buying a new fan if other testing methods did not work.

Also, even if you do command the fan to spin using a Foxwell, INPA, PASoft, etc., unless you actually measure the voltage at the connector going to the fan, using a scope or voltmeter, you won't be sure the problem is not between the Foxwell/ECU and the connector.

My Foxwell sends the control signal as well, with specifics listed by me earlier in this thread. My BMW Scanner PASoft clone thing probably used to, but decided to stop working when I tried it on this problem.

[andrewwynn]

With most of the higher end fluke DMM, they also will show you frequency and duty cycle. Even better than the rms voltage method (which is excellent research and sharing so thanks for that)

[UPGrayd]

Originally Posted by andrewwynn

Resetting an error causing trifecta won’t clear the error until you drive a bit. Did you capture the errors you cleared (I usually take pic with my phone).

The Errors I had causing the 4x4 light were 55C4 and 54C6.

[UPGrayd]

Originally Posted by upallnight

Can you explain "from the look of thing". Did you get an error code for an inoperative aux fan or were you not able to activate the fan through INPA?

I was unable to activate it through INPA. When trying to I got the following Error "ERROR_RELAIS_ZUSATZLUEFTER" (ERROR RELAY, AUXILIARY FAN according to google translate)

[wpoll]

Originally Posted by UPGrayd

The Errors I had causing the 4x4 light were 55C4 and 54C6.

The 55C4 is a comms error between the DSC controller and the transfer case controller. Many causes it seems...

The 54C6 is the classic transfer case "oil wear" error and I'm pretty sure it won't trip the 4x4 lamp (on it's own). It indicates that your transfer case need to be drained and refilled with fresh BMW Power Divider Fluid (BMW DTF1). You then need to run a reset procedure on the VTG module to reset this oil wear code (and transfer case adaptions etc.). You cannot do this with INPA - which is the main reason I got DIS up and running. you can also perform this specialised reset via a Foxwell....

[UPGrayd]

Originally Posted by wpoll

The 55C4 is a comms error between the DSC controller and the transfer case controller. Many causes it seems...

The 54C6 is the classic transfer case "oil wear" error and I'm pretty sure it won't trip the 4x4 lamp (on it's own). It indicates that your transfer case need to be drained and refilled with fresh BMW Power Divider Fluid (BMW DTF1). You then need to run a reset procedure on the VTG module to reset this oil wear code (and transfer case adaptions etc.). You cannot do this with INPA - which is the main reason I got DIS up and running. you can also perform this specialised reset via a Foxwell....

I was going to look into doing the transfer case fluid this weekend, being a lubrication issue I would rather do it sooner than later. What's involved with getting DIS going? I really dont want the car to be driven around for weeks and weeks without it being done while waiting for my Foxwell.

[wpoll]

Originally Posted by UPGrayd

I was going to look into doing the transfer case fluid this weekend, being a lubrication issue I would rather do it sooner than later. What's involved with getting DIS going? I really dont want the car to be driven around for weeks and weeks without it being done while waiting for my Foxwell.

Just hold off doing the transfer case fluid job until you get the Foxwell - it's lasted this long!

Or do the fluid change now and then do the reset later. Lots of folk never do the reset at all. Not my own preference but hey, each to their own....

As for getting DIS up and running - I'm happy to help with that if you are crazy enough. It needs a Windows PC running a VMWare Virtual Desktop application to run the UNIX-based DIS system. Then you need to set up a virtual diagnostic head emulation to connect your existing K-Line OBD cable via EDIABAS to a virtual Ethernet port in the DIS.

(Cue sarcastic comment from Andrew!!).

[UPGrayd]

Originally Posted by wpoll

As for getting DIS up and running - I'm happy to help with that if you are crazy enough. It needs a Windows PC running a VMWare Virtual Desktop application to run the UNIX-based DIS system. Then you need to set up a virtual diagnostic head emulation to connect your existing K-Line OBD cable via EDIABAS to a virtual Ethernet port in the DIS.

With a technical background in various IT areas, I'm not scared off by this...however I do know that its alot more screwing around than I am prepared to commit to with a couple of businesses, a 2 year old and the rest of the family all competing for my time and attention.....I'll wait for the Foxwell

[andrewwynn]

Originally Posted by wpoll

Just hold off doing the transfer case fluid job until you get the Foxwell - it's lasted this long!



As for getting DIS up and running - I'm happy to help with that if you are crazy enough. It needs a Win sarcastic comment from Andrew!!).

Funny guy.

Mehr Leistung für diejenigen, die 30 Jahre alte Software auf 20 Jahre alter Hardware arbeiten lassen

I have no idea how accurate that is any more than I'd know how to read the German software.

I would not mind having a craptop with the BMW suite to especially do coding but the relative ease to do virtually all the needed services put a solid win in the foxwell column.

[wpoll]

Originally Posted by andrewwynn

Funny guy.

Mehr Leistung für diejenigen, die 30 Jahre alte Software auf 20 Jahre alter Hardware arbeiten lassen

I have no idea how accurate that is any more than I'd know how to read the German software.

I would not mind having a craptop with the BMW suite to especially do coding but the relative ease to do virtually all the needed services put a solid win in the foxwell column.

Hey - I didn't say your postion wasn't justified!

For the record, I'm actually WITH you, Andrew - the Foxwell seems like a MUCH better diagnostic solution for most people... I went down the INPA/DIS path as much for the practice in the fine art of inventing new expletives as obtaining a working diagnostics system.

Didn't meant to poke fun at the topic at your expense...

No harm meant - Friede, Bruder