HuggyTheBear

Audi MMI Nav showing wrong location. The Nav showed me going across a field when i was actually on the M42 Motorway. This had never happened before, The only other symptom was I lost Dab radio a few times mainly when i started driving car for the first 30 mins. In areas where it had worked fine previously

I decided to start with the Fin Antenna as that was the only thing exposed to the elements . its acts Dab radio and GPS Antenna for the Nav. Inside the fin is a PCB which can be susceptible to Moisture and dampness getting inside. (see pics) The actual Antenna is held on by one screw positioned towards the latter third of the fin antenna. The front of the fin does not sit tightly where the rubber gasket meets the metal of the roof.

When I moved the fin antenna a slight gap appeared at the front of the fin Antenna 0.1mm but probably enough to let rain water and moisture in.

On that assumption I set about drying out the PCB of the Fin Antenna . Very difficult unless you want to take all the roof liner off with the A,B,C & D pillars removing. Audi wanted charge approx £450 all in to change Antenna which I could not justify on a part which cost £100.

I needed to get rid of the moisture and this might not be the most scientific solution but I used a hair dryer 15mins on the top around the fin antenna and 15mins from inside the car from below pointing at the roof roughly where the antenna sits overhead. I left the car overnight and started in the morning.(it was a dry night no rain) and as if by Magic my Sat Nav started working again. I repeated the procedure later that evening then used some clear silicon sealant to go round the edge of the rubber gasket and metal roof to act form a waterproof seal.

Its been 2 weeks now and i haven't had any issues with the Dab or the Nav. Finger crossed

I'm also aware this happens on all other Audi's a3, a4, a5 ,a6 and a7 with a fin antenna / Aerial so could post a link to the other forums.

Happy New Tear 2017 !

morski

You should not have lost and DAB reception as the DAB antenna is located on the c pillars.
The cheapest way to remedy this is to use a cheap gps aerial from fleabay and plug it into the back of the MMI unit and place the antenna behind the dash as high as possible.
Hopefully yours will continue to work

Greg Hutcheson

Hi, I have no sattelites being received and have therefore bought a hockey puck style gps antenna to try instead of another fin. What colour of fakra connector should I be connecting to on the back of the mmi unit?

i seem to have pink and blue connected, with nothing coming from the green one. Which one is for gps?

thanks in advance

Lp01

Thanks for sharing your problem and solution!
I have a 2015 audi TT and some days ago I washed it using a high pressure water gun. 3 days later had the same symptoms and noticed that the small gap between the fin and the car metal top was there. Several MMI resets didn’t help, obviously.
Followed your recipe and voilá, the GPS immediately started to work correctly showing the car in the right location.

numbskull

Yes I have had this problem before and it rectified itself after 3-4 weeks just before taking it for a new fin at £350 and looking back at the time I thought water problems.
Just started having same problem again a year later and guess what, it happened after a few weeks non stop rain so checked fin and yes it has movement between rubber seal and roof so will try hair dryer treatment or might try airline which is connected to a compressor in work then seal the ****** with silicone before it does it again
cheers

markjhonson

I have the same issue with my 2015 MK3 TTS. What exactly did you do to fix the issue? Can you remove the antenna without having to remove all the interior panels etc?

deezell

Just noticed this problem at the weekend. Mmi nav is showing zero satellites and I have a B105413 GPS Antenna open circuit fault. I noticed the GPS was stuck showing a location I was in 5 days previous,the same day I used a pressure washer on the car. I cant say what a TT is like, but in the A6 C7 you definitely need to drop the headliner down to reach in and undo the torx bolt. That means popping the grab handles out, they're not screwed in, just pull the pop out insert that expands the mounting. The pillar covers also, and then a struggle to unclip the headliner from behind the 3rd brake light. Frustratingly, the rear interior lamp is just too far forward of the antenna base to reach in with a torx on a ratchet, and there's a glued on solid foam support on the headliner to block your access, but if you're willing to snap this off, small hands might just squeeze in the lamp opening and reach the torx. I quit as I was worried about kinking the headliner next to the brake light. I've ordered a generic GPS antenna with a Fakra connector for €14, I'm going to pop out the mmi unit and plug it into the blue GPS antenna socket, and place the receiver part under the windscreen, maybe under the console.
Pulling the rear interior lamp opening down as far as I dared gave me this image taken by poking my phone up into the opening. It has occurred to me that by piercing the headliner exactly under the head of the torx bolt would allow the insertion of a key to loosen the bolt. I also have a little USB C probe camera that plugs into my phone and could be slid in to monitor the operation. I think you only need to loosen the torx sufficiently to contract the claws and the whole lot pops off the roof. The tiny hole needed would be almost invisible as the fabric if the headliner would just expand then contract. Its all about getting the exact spot or a few mm near it.

deezell

That wasn't too difficult. A/C pops out simply by prising both sides with a thin plastic trim tool, I used homemade one. A single 8mm bolt underneath the centre of the mmi head unit lets it out sufficiently to unclip two cables to the bottom front of the mmi, start/stop buttons and others. Once these are unclipped the unit will pull out sufficiently to see the blue Fakra connector on the back of the mmi. Put the car in drive to lean the auto stick back out of the way. I removed the fuse panel cover on the right side of the console, right hand door open (RHD car), and I placed the generic antenna through an opening in the console, placing it just above a ventilation duct I could see. I pushed some old seat sponge in which kept the antenna in and pressed up against the inside top of the dash console, out a bit from the piller, this is directly under the lower slope of the windscreen, so has line of sight through non metal materials over a good angle in all directions. Before this I had threaded the cable and connector across the interior of the steering cavity, and it was easy to guide it into the front of the A/C and MMI cavity and feed it into the space between the two units, then back to the MMI Fakra. Once the MMI was pushed in and the bottom cables reconnected, I tried it out and straight away my GPS was restored, finding 7 satellites. A/C pushed back in, cable slack tied up and fuse cover replaced, and I was good to go. A few errors to clear when I scanned, probably due to the unplugged cables.

Generic GPS Antenna with right angle Fakra connector