Summer webasto noise????

[4687ah]

Hi, I have noticed the webasto is making a noise like a fan is running on my 2006 3.0d. It kicks in and out even when the ignition is off. By that the "fan" may run for a second or two or just "pulse" but not actually run. The sound seemed like it was coming from the front of the car but that was because if the "vent pipe" that goes into the front wing making a noise. Its early days yet watching it, so i may be wrong about this bit but it does seem to activate more if you have just closed the bonnet or pressed the key fob as if its woke the car up a bit???
Any help please.
Do i get points for an out of season webasto thread?

[Horizon]

Try pulling the multiplugs out of the Webasco, just to see if the noise goes away. Could be a faulty PCB if its starting for no reason

[dobbor1]

With the hot weather and the air con on full blast, I have heard a different noise from the bonnet when I pull away in first gear then it stops in the other gears. Doesn't do it with the air con off. I assume this is normal?

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[X5Sport]

Depends upon what the 'noise' sounds like?  It could for example be the viscous coupled fan spinning up in 1st gear and with the vehicle speed noises not covering it you could hear it perhaps?

Richard

[dobbor1]

What's a viscous coupled fan?

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[X5Sport]

Is there not a fan connected to the front of the engine, as well as an electric one?  The engine driven fan uses a viscous coupling with a fluid that gets more viscous at high temps.  When cold the fan barely runs as the fluid is very runny.  I just wondered if with the extra warm weather we currently have, the fluid may be thicker and you might be hearing the fan spinning up with the higher revs in first gear.....

Richard

[4687ah]

Thanks for suggestions so far.
It cuts in and out with the car sat on the drive with no key in the ignition. I dont know if it is running when driving as you wouldn't be able to hear it.
There appears to be 3 multiplugs on the webasto, it makes no difference if you pull the single wire one or the three wire one, the only way to stop it from happening it is to pull the two wire one which is obviously the power supply due to its thicker cables. I have left this disconnected and am assuming that as the webasto is not meant to run if above 5'c then its ok to disconnect it in this way.

[jaynana]

single wire socket goes to the water pump
the 2 pin is the main power connector
6 pin has the k-bus and the works

i've heard of webos mis-behaving before - like a whirring noise (air fan) every time doors are locked/unlocked, etc. not sure what causes this confusion.

key doesn't have to be in the ignition at all because the car is 'awake' and the comms are active.

all these units of course communicate on the k-bus, incl the webo. one guess is that a webo pcb gone slightly mad could be interpreting a msg sent to a different unit as a command to the webo to start work.

on the other hand it could be rogue messages.. although i doubt it.

[omodos]

[quote="4687ah"]
Thanks for suggestions so far.
It cuts in and out with the car sat on the drive with no key in the ignition. I dont know if it is running when driving as you wouldn't be able to hear it.
There appears to be 3 multiplugs on the webasto, it makes no difference if you pull the single wire one or the three wire one, the only way to stop it from happening it is to pull the two wire one which is obviously the power supply due to its thicker cables. I have left this disconnected and am assuming that as the webasto is not meant to run if above 5'c then its ok to disconnect it in this way.
[/quote]

did you get any dash fault code by pulling the plug on the webasto? i wanna do the same or better still pull fuse 59 from the glovebox fuse area that is for the auxiliary heater webasto, just a tad concerned it will throw a fault code though.....

[4687ah]

No it didn't throw up any codes. I left it unplugged for a week or so then plugged it back in and the fault never reoccurred.