2000 A6 4.2 Quattro Transmission Problem
 

Hi,

This afternoon I lost my reverse gear. My car stoped shifting into reverse. No light came on, no indication of any problems. Drive works fine. Does any one had similar situation? Also are drive and reverse connected in any way, should I expect to drive to fail on me as well? Please advise.

Could it be the button?
 

I've had the button stick such that I couldn't get it into park and remove the ignition key. A search here found it to be a common problem. If you don't have a warning light, then perhaps this might be related to the button/interlock system?

<a href="https://forums.audiworld.com/a6/msgs/266828.phtml">Key stuck in ignition, but a search turned up the fix...</a>

Re: Could it be the button?
 

<center><img src="http://alex.automatedfinancial.com/A611/3.JPG"></center><p>Thanks, for response.

Would you please care to illeborate. My thinking is that I lost my reverse gear permanently. I am able to put it into reverse, but nothing happans. The only thind that puzzels me, is how come there is no warning lights or anything of that nature.

Thanks, Alex.

Almost sounds like it might be the solenoid that enables Reverse.
 

<center><img src="http://pictureposter.audiworld.com/1018/a6_service_013.jpg"></center><p>When you open up the transmission, there are a pile of solenoids that change the transmission hydraulic paths to make it do it's thing. It almost sounds like the "Reverse" solenoid may have failed, or there's a bad wire or connection to it, something like that.

The picture above is from the A6. I don't have a similar picture from the A8, but the transmissions are very similar. The solenoids are the dark cylinders at the back (bottom of the picture), and you can see where the internal (to the transmission) wiring harness runs back to them.

Also, you should see if there are any codes set with a VAG-COM, though I would have expected a
 

transmission code to have also lit the CEL.

Somebody just reported the same exact problem on audifans A8 list (with an A6 4.2)
 

She lost reverse, just like you said.

Your tranny is the same one as in the A8. It could be a solenoid, or maybe something with the tranny fluid and filter. I would get it changed asap.

I don't think it's the shift lock solenoid, that's on the shifter and if you can physically get the shifter into "R", then it's working. It's just a mechanical solenoid on the shifter.

I doubt it's one of the 8 solenoids either, because there is no one solenoid specific to the reverse gear. However, there is "clutch C" which is specific to reverse.

You need to plug the ross-tech software into your car and see if you have any fault codes.

Then I would get the fluid and filter changed ASAP. This could solve your problem. I've already seen it solve "limp home mode" problems with significant foreign material because of wearing components in the tranny.

Go to <a href="http://www.audipages.com/Tech_Articles/auto_transmission.html">audipages transmission page</a>, you'll probably find more information than you can digest in a few minutes.

Get the fluid and filter changed ASAP!

pw

Re: Almost sounds like it might be the solenoid that enables Reverse.
 

<center><img src="http://alex.automatedfinancial.com/A611/4.JPG"></center><p>Thanks for the input, I will get the oils and filter changed ASAP. So basically I should be ok with the drive gear, right? I am taking it to the dealer on Tuesday. What do you think it would set be back to. Any ideas?

Thanks for your replies, Alex.

The dealer will tell you 10K for a new tranny
 

Tell them you want a filter and fluid change, about $350.

pw

Re: The dealer will tell you 10K for a new tranny
 

What about replacing solinoid, how much it could possibly cost?

Likely not solenoid
 

Paul says that there isn't a reverse solenoid. I made an assumption that one of the solenoids was for reverse, but he says above there isn't a single reverse solenoid, and he knows these transmissions better than I do.

If I were you, I'd pull the codes with a VAG-COM or VAG-Tool, and get the transmission serviced - drain fluid, drop pan, replace filter, re-fill. A lot of transmission ills get fixed with that, and it's certainly worth a try for the $300 or so it ought to cost.