W639 Viano - Ticking Heater/Fan when Cold

[bogcaster]

Help/Guidance required - Has anyone ever experienced a faint ticking from behind the dash that eventually goes away after 10 minutes after a cold overnight rest.

Its not to do with the engine as it ticks even before the engine is started. And its not to do with the Ventilation Fan as that's set to Off (Zero Speed). Unless the ventilation fan is cooling something else even if its set to zero.

I'm already aware that the heater drum flaps move for about 10 seconds after the ignition electrics come on. I don' think its that as it lasts much longer but it could be related - not entirely ruling it out. The colder the overnight rest, the longer it ticks for.

I have my suspicions it could be related to another fan, i.e is there an ecu or system fan somewhere. As when the car is turned off, a system fan somewhere behind the dash continues to run for a few minutes, presumably to cool some electronics or ecu down.

Everything works fine - its just a bit iritating and not knowing if it is going to eventually fail while I'm in the middle of nowhere. I didn't notice it back in the summer though.

Any help or thoughts appreciated.

 

[stumpy1]

Mine does it too (as well as other strange things)

 

[BTB 500]

There is a cooling fan for the dash electronics, which does run for several minutes after switching off. Could be that.

Silly question - it's not the CD player?

 

[rizzer]

I noticed a ticking noise behind the dash this morning when cold, sounds the same, faint and a constant tick, it didnt change with engine speed either. It appeared to be more on the passenger side. I'll listen more carefully from now on.

 

[BTB 500]

I think the electronics cooling fan is on the passenger side.

 

[bogcaster]

Thanks all. I had another very very close listen this morning. Its definitely not the CD Player and its directly under the two heater control dials. Its not coming from the passenger side. I am pretty convinced its to do with the heating/cooling system.

I am trying to work out if this is normal. When the ticking starts, on turning the heat level to cold, it goes but it comes back when turning it back to hot and the tick kicks in from the half way temperature. I actually thinks its some actuator behind the dash. The key point is that the ticking keeps going for seveal minutes as opposed to just a few seconds as it should be.

The ticking also restarts when the Residual Heat Recycle is switched on after the key is pulled out of the ignition. Which is why I am pretty sure its some control mechanism related to the heating/cooling system.

Has anyone taken the heating controls off from the dash on a Vito or Viano ? I'm pretty comfortable in doing this if someone can give me some guidance. It may give me a chance to diagnose more closely.

Thanks again.

 

[salmezz]

Mine does it aswell but stops after i punch the dash to the right hand side of cd player!!

 

[rizzer]

We have two Vitos and both have this ticking noise, I've put my ear to both rotary heating controls and it definately sounds like its behind these. Is it normal or is it a fault? Everything seems to work ok otherwise.

 

[BTB 500]

No ticking noise from ours.

 

[sunderlandshirt]

Yep mine does this as well.
Don't these have some sort of pre-heater that warms up the heating system before you get any heat into the engine? Always thought it was that as it goes off after a few mins

 

[rizzer]

I still get the ticking noise from behind the heater controls,not all the time though. I am sure its from the rotary temperature control, when it was ticking this morning I turned the temp down and it stopped, turned it up and it started ticking again. I can hear an actuator operating and I assume the ticking is coming from this actuator. Does this happen with others that have the ticking noise. Would this be a fault covered under warranty?

 

[bogcaster]

Fianlly got it sorted. The ticking was an actuator behind the rotary dial which was diagnosed and repaired under warranty - finally! I had to leave the Viano at the dealership overnight for them to hear the noise in the morning. I drove there next morning in my other car to make sure they could hear the irritating noise.

Apparently, there are lots of actuators but because they did it, I'm not sure which one it was. Rizzer - get yours done under warranty if still possible.

Had other things done under warranty too including anti-roll bar linkages and bushes which were causing a knocking sound just after full lock. It seems that these wear out frequently after discussing with a Vito owner friend of mine.

 

[rizzer]

Good to hear you got your ticking heater sorted Bogcaster. I'll get mine booked in soon, thanks.