Multifunction Computer - Data Lost

Hi All,

I have recently encountered a problem with my 2006 Passat Estate. I have an S model which has the standard multifunction computer which reports average speed, average fuel consumption etc. When I started the car the other day I noticed all of the recorded data in the multifunction computer was at ‘0’. My wife had just filled the car the previous day with fuel and I assumed she had zeroed everything when arriving home.

I went on a 20 minute journey and parked up for around an hour. When returning to the car I noticed that the average speed, fuel consumption, engine running time etc had been zeroed. The second Trip meter, which is displayed under the Total mileage display, is still reporting the correct miles covered and only the multifunction computer is affected. If I turn the engine off for a few minutes and back on the data is retained. The engine needs to be off for around 1 hour before everything is reset to '0'.

Has anyone heard of this before? Is the multifunction computer data battery backed by a separate battery from the main car battery and this battery just needs replacing (Probably not but just wishful thinking on my part)? As most things are governed by sods law the car is just 20 days out of its 3 year manufacturing warranty! Any insight or suggestions would be much appreciated.


Many Thanks,


Alan

There are two trip computers, one is per journey (indicated by a little "1") and the other is long-term (indicated by a little "2").

Trip computer 1 will reset after 2 hours (well it should be 2 hours) back to zero. Trip computer 2 will retain the data until it is reset or the battery is disconnected.

Hope that helps :)

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Originally Posted by shark_90

There are two trip computers, one is per journey (indicated by a little "1") and the other is long-term (indicated by a little "2").

Trip computer 1 will reset after 2 hours (well it should be 2 hours) back to zero. Trip computer 2 will retain the data until it is reset or the battery is disconnected.

Hope that helps :)

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Hi Shark,

Thanks for the information. It seems like everything the multifunction computer records get set back to '0' and not just mileage. Total trip miles, total running engine minutes, Avg MPG and Avg speed. It has been working fine since I had the car and in the past all the data was stored in the multifunction computer for me to view. I believe the only way you are able to zero all the data is to press and hold the button on the wiper stalk. I suppose a battery disconnect would wipe the data but this problem happens every time I turn the engine off for longer than a few minutes. :(

Try a battery disconnect - it's no different to rebooting a PC in some ways. Turning off the ignition is a bit like a PC going on standby.

Quote:

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Originally Posted by Quatrelle

Try a battery disconnect - it's no different to rebooting a PC in some ways. Turning off the ignition is a bit like a PC going on standby.

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Thanks Quatrelle,

This may sound like a silly question but is there anything to watch for when disconnecting the battery? I would imagine I may have to re-enter the security code for the radio but is there any other adverse affects caused by a battery disconnect/re-connect?

My previous car was a 98 Polo and there isn't much in the way of electonics in there so doing the above didn't bother me :p

Disconnecting the battery does not lose the radio code or the data stored and displayed. I think Shark was trying to tell you to play with the wiper stalk to make sure you are on the correct setting. One setting is for "current trip" and that does reset. The other setting doesn't reset. Look for a little "1" or "2".

Quote:

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Originally Posted by Quatrelle

Try a battery disconnect - it's no different to rebooting a PC in some ways. Turning off the ignition is a bit like a PC going on standby.

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Good analogy, that.

The long term trip computer also resets back to zero every 100 hours driving time if leave it running long enough.

aperson

Use the button on the bottom side of the stalk to change between the short-term readings (denoted by the figure 1 on the readout) and the long-term readings (2).

As the others have said the short-term readings zero themselves after the ignition has been off for an hour or two, but the long-term readings will be retained.

You can use the button underneath the stalk to reset either the short or long-term figures by holding it down for a second or two.

So pressing the button briefly will change between the short-(1) and long-term(2) readings, but keeping the button pressed will zero whichever option you're in at the time.

If you've had the car for a while I'm surprised you've just noticed that the short-term (1) readings zero themselves, but maybe you've been in the long-term readings (2) all the time and maybe you've accidentally changed over to (1).

Thanks to everyone for the advice offered. The car had always been reporting the long term figures and my wife must have switched it to short term :o Since I don't drive her car that often I didn't release it had this option and neither did she!

Thanks again.