Climate Control Linked To Engine Temperature

[colin]

Following a major service including new VW ignition leads replaced because the car (VW Sharan 2.8 vr6 1996) was idling roughly, I have found that the water temperature guage rises to over three quaters. The problem now is that the cruise control fans do not operate until the water temperature reaches this high point! (ie, heavy queing traffic). Once driving normally the temperature drops to midway and the air con stops (although the buttons and display all work OK.

I would appreciate any thoughts on this weird situation.

[colin]

Additional info

Following a major service including new VW ignition leads replaced because the car (VW Sharan auto 2.8 vr6 1996) was idling roughly, I have found that the water temperature guage rises to over three quaters. The problem now is that the climate control fans do not operate until the water temperature reaches this high point! (ie, heavy queing traffic). Once driving normally the temperature drops to midway and the air con stops (although the buttons and display all work OK.

I

One other point is that the Sharan is converted into a wheelhome camper van which has a 12volt water heater fitted. This is wired up so it only comes on when the engine is running (via a pair of relays & aux battery) . Since the climate fault the water heater is only working when the climate fans start! It seems a 12v trigger voltage to the water heater has been tapped from the heating system (ecu). My garage state that my engine cooling fan is only running at full speed and they are going to replace the resister unit.

The cruise control has also stopped working. Garage states all vaccum system is OK with no leaks so back to electrical fault?!

I would appreciate any thoughts on this weird situation.

[BrianH]

Are you sure both fans are actually working when they are turned on to full speed?

[colin]

Hi,

To be honest I do not know! I have relied on the garage who have had it 3 times looking at different faults. The last time they had the wrong part (resister unit) delivered.

Do you mean the two fans on the front of the radiator?

Yesterday I found that when I returned home the engine was hot but this time the CC fans did not come on BUT when I turned off the ignition all the fans stopped until I removed the ignition key when a fan started and ran for a few minutes!

I will run the car today and see which fans come on.

Thank you for your interest & sorry for long reply!

[BrianH]

Yes. One afaik should come on with the ac on. If I were you I'd get a vcds lead - they can be had cheaply off eBay and do a scan for codes. I'd suspect you might find one of the fans seized or failing to turn personally.

[colin]

Hi

Thanks. I will try to check out as much as I can regarding engine fans, a/c fans, engine temperature etc.. It will be pot luck if the a/c comes on or not!

Where is the socket for the vcds lead. Is it within easy reach?

[BrianH]

Lift the ashtray out its underneath

[colin]

Hi,thanks

 

I have had vcds lead delivered this morning but it will take me a while to get it up & running.

[colin]

Set up lead and found it did not recognise my Sharan. (Not compatible) so back to drawing board- and garage.

Thanks for your interest.

[BrianH]

1) What lead have you got?

2) Are you using the vag-com software from the disc rather than vcds lite from Ross-tech? Its the same program, but much newer version.

3) What error are you actually getting?

[colin]

Hi

It was an inexpensive e-bay version listed as "USB Cable KKL VAG-COM 409.1 OBD2 II OBD Diagnostic Scanner VW/Audi/Seat VCDS"

I had looked at the compatability list and saw the Alhambra and assumed it was the same. The Sharan was not listed. The supplier is happy to accept my return and refund me.

 

I used the software that was supplied on disc with the lead which installed with no problem. I tried it on both a XP laptop and a win 8.1 laptop.

Both times I got the same message "Port status:OK, Interface not found!. Contact hardware supplier for assistance" when I tried the initial install test.

 

The lead was to give me an idea of what is going on in the car. Even if it worked I would probably be unable to follow any fixes!

 

Regards

[BrianH]

That should be fine it sounds like mine, The message to me sounds like you haven't told it the right com port on setting it up.

 

First thing plug the interface into the diagnostic socket on the car and switch the ignition onto position 2 (engine doesn't need to be running, but dashboard lights showing battery etc should be lit)

Plug the usb lead into the laptop

 

If you goto start>run type in devmgmt.msc this should open device manager - expand the ports section and find what it says the port assigned to the "usb serial port" is - you want between com1 and com4 for vcds, I'd suggest you set it to com2 to start with. Then ok your way back to the desktop

 

Open vcds-lite (if you've installed vag-com its an older version of the same program - you can download the current version from http://www.ross-tech.com/vcds-lite/download/index.html) and on the first page select options, then in the first box inside the options select com2 (or whichever one of the ports you've used) and hit test again.

 

If you haven't switched the ignition on you will get interface not found, if you've selected a port thats in use by something else you will get the same.

 

The Sharan and Alhambera are effectively the same vehicle - even the Ford in the 2.8 version is the same thing with different badges on it, so the lead should be fine assuming the lead actually works.

Edited June 5, 2015 by BrianH