Double_Dip_A6

I have a 2007 Q7 (S-Line with 21" wheels) which has been my pride and joy, but now she is starting to show her age. I recently had a fault on the Blind Spot Indicator … each time you press the button on the drives door the "sensor fault" is displayed and the dealer wants over $4000 to replace. Seems Audi has updated the design since 2007 and you have to buy them in pairs. Also the dealer indicated it was quite an involved process to align the sensors after the installation. Has anyone on the forum tried a DYI replacement?

I am also about tp go down in size from the 21" wheels for a better ride and wider range of all season tires. Just moved to Washington DC Metro area and need better winter tire options .. and MORE sidewall.

Thanks in advance for your comments/feedback.

tigerwillow1

I had a similar but different issue with my '08. While just driving down the road, the Audi Lane Assist module went belly-up. This is a simpler system with all of it integrated into a single module that's pretty easy to swap out. I bought a used module on ebay for under $100. It took some recoding with VCDS and has been working well ever since. It also "requires" a dealer-only alignment that costs at least a few hundred $. Fortunately, the alignment in the one I swapped in is close enough for me. Might even be as good as the original as I'm not able to judge it that closely. I'd suggest dumping fault codes in the hope they might pinpoint the problem to a single component. Could even be a dirty connector if you're lucky.

chingwodapigu

So when I had this same issue on my '07 4.2, it was the driver side "slave" module that had died. There is one module in each side of the rear bumper. A new module ran about $450 iirc, and the calibration actually takes a while, I think at least an hour and a half., and the first time it was done incorrectly, so I had it recalibrated again for free. Entire bumper must be removed to access the modules, and VAG and a calibration rig is needed to do the calibration correctly (and a good tech, not the lazy idiot that did my first calibration). I was told initially that they might need to replace both modules, but in the end, only the dead slave module needed to be replaced.

red1bw

Just like Tiger, my lane change went belly up while driving on a long and rainy road trip. VCDS stated it was a defective slave unit (left). I replaced the slave unit with a similar used one (same year and part number) and still have the error, however, I have not yet played with VCDS yet. The actual changing of the slave only required removal of half the bumper (1 decent youtube video on this). Once I loosened the left half of the bumper, I inserted a 2x4 scrap board sideways to hold the bumper out while swapping the module. The only other item not covered in the video for bumper removal were the screws on the bottom rear; but I suspect they are only on the 4.2's given the bottom treatment in those years. On 2007 and 2008's the module is attached to the inside bumper. It only had 2 screws and a wiring harness (after undoing the 2 screws it slides sideways); so an inspection mirror and flashlight will help. The module fits solidly in the bumper. I suspect any module that worked properly on one Q7 would be close enough for the other. If I recall, the Audi manual says to re-calibrate the system after any bumper removal and re-installation; but that simply isn't done based on techs I've talked to or DIY who have removed and re-installed their bumpers.
Any insight by Tiger or others on the VCDS area would be appreciated. Hopefully by deleting the previous error codes it will recognize the new slave module; but I doubt it is that easy.

tigerwillow1

I made a major terminology boo-boo in my post above, using the invalid term "lane change assist". The module I swapped was for "Audi Lane Assist". This thread is about "Audi Side Assist". My intended contribution was that used modules can possibly be found on ebay at a reasonable cost, with the possibility of working. Audi Lane Assist is the module at the top center of the windshield that warns when the vehicle strays out of its traffic lane, and has nothing to do with Audi Side Assist. I've had trouble keeping these similar names straight before and apologize for any confusion. I'm going to fix the earlier post.

The VCDS change I had to make was to re-code the module to indicate no air suspension. The car it was pulled from had the air suspension and the module I swapped in wanted to communicate with the air suspension module. Maybe an issue with Audi Side Assist, maybe not.

red1bw

Thanks Tiger. Again, I haven't played with VCDS yet, but if I have any success I will update this thread. I don't even know for sure if the swapped module is good or if this is even possible without dealer equipment. As far as swapping modules in another Audi and other cars I have generally had success once I figure out the part versions and finally find what is needed.

dukesean

Hi red, make sure the module is from similar year Q7 if you are trying to avoid dealer visit like me. A8 use same module as Q7, and that calibration would be different.
Mine is 07 4.2 with A version and A firmware module. B version would not communicated with A version I have. But I want a newer module in hope for longer lifespan, so I got the A version with B firmware. It works right away as now you won't get error message when press side assist switch. Then clear error code and system works as it should.
Hope this helps. Good luck.

red1bw

How do you know the firmware version?

dukesean

The old part number for slave, driver side, module is 4l0907568A
And firmware will show as SW4l0910568A on module, like this one


​https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F32 3546115542

or SW 4l0910568B like this

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F15 3112558936

Also theret is manufacturer date you can see so you can get a newer one.

Double_Dip_A6

Thank you for the comment. I definitely appears that the unit in the left bumper as well as the module by the driver's door that engaged the system are both bad. Looking in eBay and other sites for parts.

I also recently purchased a VAG unit and have started playing around with it. I did get to the screen that shows the settings for the trailer and at least verified that US is selected. This VAG thing will take some time to figure out. I am a very technical person, but this is a new world for me.