What does this do?

[BigDaz]

I have now owned my S4 for 1 week
On sat I discoved a wire with a connector in behind a flap above the rear view mirror. It appears to be connected to the windscreen or very close to it - any ideas what this is for (or should be connected to)?

Also with 1 week & 1.5 tanks of fuel in, I am averaging 28.1 MPG ( this involves a fair bit of "testing" the new car too ) Is this OK?

Cheers

Daz

[MarkB]

Don't know about the wire but your MPG is much higher than most of us manage. Are you only driving down hill?

[JonnyX]

Check your MAF

[BigDaz]

Why would I need to check the MAF? Surely this only needs checked if MPG is low?
How do you check it anyway?
Daz

ps. only driving downhill one way

[buzzard]

a guess

could be radio antenna.
(cus they havent got on anywhere else)

[ChipHazzard]

I'd say it could be for the self dimming rearview mirror option but will stand corrected when a more knowlegable members comes along

[dazzer]

Agree with Chip - It could be that the car had the self dimming mirror option and it's been taken out for transplant into another car. I was thinking of doing that myself by robbing my A4 but was not sure if the wiring was already installed...

[ChipHazzard]

It could also be that the car was pre-wired for it from the factory, If I remember when i get home i'll have a look at mine

[MarkB]

I don't think they are pre-wired. I wish they were, I would do the upgrade if I had the wiring in place. Happy to be proven wrong..

[oliew]

i think the radio antenna is in back window? could be wrong tho

[BigDaz]

Mines is the Avant, So I have an ariel on the roof, so its not that
Should I look for a plug in the back of the mirror? or see if its a replacement screen?

Daz

[MarkB]

I think the dimming mirror has an arm down from the roof to the mirror. The standard mirror just sticks to the screen. Maybe the screen or mirror broke at some point and was replaced with a normal mirror

[ZeroK66]

Wow... 28MPG - something may be wrong! MAF underreading mean the car would be underfueled. The only way to check MAF is to connect up VAG-Com and take it for a flat out drive. Peak MAF reading should be about 215 standard & 250+ for a chipped car.

[SimonS4MTM]

I can get 30mpg, nothing wrong with my car

[BigDaz]

Hmm, being an ex scooby owner, driving the car flat out if it has suspected MAF issues does not sit well with me. Any other (less dangerous) methods of testing ?

Daz