All dash warning lights coming on

[Etch]

Hey all,

I've had this 2012 Audi A6 since 2017 and have suffered this problem since then.  Sometimes it appeared after a few months, sometimes after 6 months, sometimes daily for a week, just random.

The problem: When driving, randomly a whole load of warning lights and messages would come up on the dash, sometimes speedometer dies and comes back (could even be gone for many minutes, which is not a condition to drive in, have to rely on Google Maps for speed until I can stop somewhere), power steering sometimes goes, cruise control gone, sometimes AC, ABS and anything break related mainly.  After switching car off the parking red light flashes as if it doesn't come on ... but I leave the car for an hour or so and then all is fine, next time it starts there are no signs of problems.

I've had it checked in many garages and nobody could figure it out (well, all they did was plug in the machine and see no error codes showing the fault).  I took it to Audi themselves for diagnosis a couple of years back who guaranteed they would find the problem, but in the end could not.

Over the past year I have been toying with a clue that my wife gave me ... she said whenever the problems start it's because somebody has moved in the back seat, her or my child.  She is right .... as soon as there is excessive movement in the back the lights/warnings come on (not all the time, I can still have a good run before it happens again, I suppose it depends on the amount/intensity of movement)

What would this mean?  Is there some loose cable under the back seat, center console, under the carpet?  Was sad that Audi couldn't resolve it despite charging per hour for diagnosis.  I need to figure this out and it doesn't seem like it should be a big problem to resolve knowing that movement in the back triggers it.

I have uploaded a video showing some of the problems: 

Many thanks

 

Edited April 29, 2022 by Etch

[Steve Q]

Welcome to the forum you'll find the members on here are a friendly and helpful bunch 🙂 sorry to hear of your situation. I've found this link which might help: 

https://www.vwaudiforum.co.uk/forum/showthread.php/197475-A6-Avant-C7-2014-Dead-instruments-MMI-screen-and-centre-console-controls 

I think your wife could be onto something too. As the battery is in the boot so all the cables have to run from that under the rest seat to the front of the vehicle. This is significant as a dieing battery can often throw up all sorts of fault codes and electrical issues when there's not enough power reaching the cars systems. 

I doubt it's the battery in your case but it's definitely worth seeing if the cables from the battery to the front a loose etc. 

I think the rear seat should be taken out so the area can be inspected. I'd recommend an auto electrican for this due to the complexity of the job to find the fault. 

Here's advice on removing the rear seat: 

the front edge of the bench has 2 metal tabs that press fit into rather fragile plastic retaining clips. Plan on having replacement plastic clips handy if you do remove the rear bench.

It's my understanding you should be able to pull straight up and release them. The plastic clip part number is: 4LO-886-373 left and right. Just incase they do break. 

[Magnet]

Hello Ehsham,

The battery is always the first suspect in such cases. If this were mine, I would be getting it checked using professional equipment. 
Kind regards,

Gareth. 

[Etch]

On 4/30/2022 at 6:35 AM, Steve Q said:

Welcome to the forum you'll find the members on here are a friendly and helpful bunch 🙂 sorry to hear of your situation. I've found this link which might help: 

https://www.vwaudiforum.co.uk/forum/showthread.php/197475-A6-Avant-C7-2014-Dead-instruments-MMI-screen-and-centre-console-controls 

I think your wife could be onto something too. As the battery is in the boot so all the cables have to run from that under the rest seat to the front of the vehicle. This is significant as a dieing battery can often throw up all sorts of fault codes and electrical issues when there's not enough power reaching the cars systems. 

I doubt it's the battery in your case but it's definitely worth seeing if the cables from the battery to the front a loose etc. 

I think the rear seat should be taken out so the area can be inspected. I'd recommend an auto electrican for this due to the complexity of the job to find the fault. 

Here's advice on removing the rear seat: 

the front edge of the bench has 2 metal tabs that press fit into rather fragile plastic retaining clips. Plan on having replacement plastic clips handy if you do remove the rear bench.

It's my understanding you should be able to pull straight up and release them. The plastic clip part number is: 4LO-886-373 left and right. Just incase they do break. 

this is useful information, thank you kindly.  I didn't realize the battery was in the boot, I don't know much about cars and in my mind they have always been at the front.  It's useful information

[Etch]

On 5/1/2022 at 9:22 AM, Magnet said:

Hello Ehsham,

The battery is always the first suspect in such cases. If this were mine, I would be getting it checked using professional equipment. 
Kind regards,

Gareth. 

Great, I will get it checked, thanks Gareth

[Steve Q]

35 minutes ago, Etch said:

this is useful information, thank you kindly.  I didn't realize the battery was in the boot, I don't know much about cars and in my mind they have always been at the front.  It's useful information

You're welcome 🙂

[Etch]

On 4/30/2022 at 6:35 AM, Steve Q said:

Welcome to the forum you'll find the members on here are a friendly and helpful bunch 🙂 sorry to hear of your situation. I've found this link which might help: 

https://www.vwaudiforum.co.uk/forum/showthread.php/197475-A6-Avant-C7-2014-Dead-instruments-MMI-screen-and-centre-console-controls 

I think your wife could be onto something too. As the battery is in the boot so all the cables have to run from that under the rest seat to the front of the vehicle. This is significant as a dieing battery can often throw up all sorts of fault codes and electrical issues when there's not enough power reaching the cars systems. 

I doubt it's the battery in your case but it's definitely worth seeing if the cables from the battery to the front a loose etc. 

I think the rear seat should be taken out so the area can be inspected. I'd recommend an auto electrican for this due to the complexity of the job to find the fault. 

Here's advice on removing the rear seat: 

the front edge of the bench has 2 metal tabs that press fit into rather fragile plastic retaining clips. Plan on having replacement plastic clips handy if you do remove the rear bench.

It's my understanding you should be able to pull straight up and release them. The plastic clip part number is: 4LO-886-373 left and right. Just incase they do break. 

I decided to confirm that the battery was in the boot today.  I lifted up the spare tyre and confirmed this ... but the strange thing is since I did this now I have this problem permanently.  The car is just acting like it's possessed. speedometer is dead, power steering dead, whole load of warning lights and constant beeping .... seems like something got triggered but not sure what.  I checked the battery and it was at 12.5v resting and over 14v running.  no cables looked loose ... I also disconnected the positive/negative terminals and re-attached them, all clean and tight.

No idea what happened just from lifting the spare tyre and looking inside ... now there is no need for rear seat movement.  

Well at least the symptoms seem to occur permanently, it will be easier for someone to diagnose. (I will start car after a good night's rest to see what it does tomorrow)

[Magnet]

Hello Ehtsham,

Great that you have found the battery, and you say you have checked the voltage, and indications are that you consider the battery to be OK on your test. 
The problem is that your battery test is about as effective as fitting an ashtray to a motorbike. Your battery test equates to testing its capacity to deliver a current load in terms of milliamperes, whereas the car’s starting current demand is measured in hundreds of amps - so the test is ( generally) meaningless. 
If you have another peep at the earlier post, you will see ‘….get it checked using professional equipment’. 
If this were mine, I would be taking the car on at least a 10 mile run and getting the battery tested - Halfords can do it, but their equipment may not test all the parameters that the car’s battery condition monitor ( if fitted) monitors. 
 

So one step at a time. Get it checked and if they say it’s below par, then happy days for you, but not for your wallet. Halfords can sell you batteries at a price. Personal view - I always buy my  batteries online from specialist retailers such as Battery Megastote, Tayna etc ( there are more, and I don’t have any connection with any). I buy Varta or Bosch and only choose their 5 year warranty grade. That way, I get good batteries generally cheaper than Halfords. 
Kind regards,

Gareth.

p.s. If Halfords declare your battery to be serviceable then please come back to us. 

[Steve Q]

6 hours ago, Etch said:

I decided to confirm that the battery was in the boot today.  I lifted up the spare tyre and confirmed this ... but the strange thing is since I did this now I have this problem permanently.  The car is just acting like it's possessed. speedometer is dead, power steering dead, whole load of warning lights and constant beeping .... seems like something got triggered but not sure what.  I checked the battery and it was at 12.5v resting and over 14v running.  no cables looked loose ... I also disconnected the positive/negative terminals and re-attached them, all clean and tight.

No idea what happened just from lifting the spare tyre and looking inside ... now there is no need for rear seat movement.  

Well at least the symptoms seem to occur permanently, it will be easier for someone to diagnose. (I will start car after a good night's rest to see what it does tomorrow)

At least now with a permanent issue it'll be easier to diagnose. Good effort with your diagnostics so far. As Gareth says I'd still get this to a garage. Any decent garage will have a battery tester (my local one certainly does for example). Besides getting the garage to do a battery test m, a diagnostic check is the next sensible option.  Out of curiosity the battery or boot didn't have signs if water ingress did it? 

I ask as water into any electronics with Audi's causes them to go haywire and do some strange things. 

[Magnet]

Hello Steve,

Unfortunately the test carried out is largely meaningless ( except for the when-running voltage) since it is not an on-load test. 
You are correct in saying that any garage will have a battery tester, but things have moved on, and battery testers which were once adequate, may no longer be, and may not/unlikely to be able to evaluate all of the battery’s characteristics that the car’s battery condition monitor assesses on going. In other words, the testing equipment may not longer be adequate and meaningful, but obviously far more go/no go that a simple multimeter. 
Kind regards,

Gareth. 

 

 

[Etch]

7 hours ago, Magnet said:

Hello Steve,

Unfortunately the test carried out is largely meaningless ( except for the when-running voltage) since it is not an on-load test. 
You are correct in saying that any garage will have a battery tester, but things have moved on, and battery testers which were once adequate, may no longer be, and may not/unlikely to be able to evaluate all of the battery’s characteristics that the car’s battery condition monitor assesses on going. In other words, the testing equipment may not longer be adequate and meaningful, but obviously far more go/no go that a simple multimeter. 
Kind regards,

Gareth. 

 

 

Thanks Gareth and Steve. I dropped the car with an auto electrician today, let's see what they can find. He also mentioned that audis tend to get water inside, and looked around battery area and passenger seat floor, didn't spot anything. But I've left the car there for diagnosis as the problem is permanent now.

[Steve Q]

2 hours ago, Etch said:

Thanks Gareth and Steve. I dropped the car with an auto electrician today, let's see what they can find. He also mentioned that audis tend to get water inside, and looked around battery area and passenger seat floor, didn't spot anything. But I've left the car there for diagnosis as the problem is permanent now.

Yep they do love water ingress. Please keep us posted on how you get on 🙂

[Etch]

On 5/9/2022 at 6:44 PM, Steve Q said:

Yep they do love water ingress. Please keep us posted on how you get on 🙂

The mechanic called today and said he disconnected a cable to the ABS unit and reattached it, and all the warning lights went away.  He is puzzled as well what the actual problem is.

I have a feeling I will get the car back without any identifiable cause and after some days/weeks the same issue will re-occur.

I told him to keep investigating, the problem isn't fixed ... just hidden again.

[Steve Q]

16 minutes ago, Etch said:

The mechanic called today and said he disconnected a cable to the ABS unit and reattached it, and all the warning lights went away.  He is puzzled as well what the actual problem is.

I have a feeling I will get the car back without any identifiable cause and after some days/weeks the same issue will re-occur.

I told him to keep investigating, the problem isn't fixed ... just hidden again.

Keep us posted. It might be worth it going to Audi. 

[Etch]

3 minutes ago, Steve Q said:

Keep us posted. It might be worth it going to Audi. 

I already did that 2 years ago, they couldn't find anything

[Steve Q]

1 hour ago, Etch said:

I already did that 2 years ago, they couldn't find anything

Sorry I should have said if the lights are on permanently then it might be worth getting Audi to take a look. 

[Etch]

8 minutes ago, Steve Q said:

Sorry I should have said if the lights are on permanently then it might be worth getting Audi to take a look. 

That's the problem, the lights are not permanently on now. Back to being hidden gremlin again.

I wish I knew about cars. I am a software developer so have the problem solving mindset, just have no idea about car electrics

[Magnet]

Hello,

You don’t tell us whether your auto electrician confirmed that the battery was serviceable via. his test. 
Kind regards,

Gareth. 

[Etch]

On 5/11/2022 at 7:36 AM, Magnet said:

Hello,

You don’t tell us whether your auto electrician confirmed that the battery was serviceable via. his test. 
Kind regards,

Gareth. 

Hi there, yes he did battery test and said its running below expected capacity. He doesn't think battery has anything to do with the problem but I will replace it anyway.

I have the car back now, time will tell what will happen. When he disconnected and reconnected the abs module cable the warnings went away, hopefully it was just a dodgy connection there (doesn't explain the back seat movement or lifting the boot tyre to make problem permanent) ... but let's see.

Thx guys, your input has been very valuable.

[Steve Q]

1 hour ago, Etch said:

Hi there, yes he did battery test and said its running below expected capacity. He doesn't think battery has anything to do with the problem but I will replace it anyway.

I have the car back now, time will tell what will happen. When he disconnected and reconnected the abs module cable the warnings went away, hopefully it was just a dodgy connection there (doesn't explain the back seat movement or lifting the boot tyre to make problem permanent) ... but let's see.

Thx guys, your input has been very valuable.

You're welcome, glad we could help. Fingers crossed its just a battery 🤞

[Frank Cook]

On 5/14/2022 at 11:10 PM, Steve Q said:

You're welcome, glad we could help. Fingers crossed its just a battery 🤞

Had similar problem in my 66 A6 Allroad - ended up new ABS unit and battery - very expensive!

[Johnoaudia6]

Hey - did the replaced battery solve the issue in the end? Got the same crazy problem on my A6 2015…

 

Thanks!

[Etch]

20 minutes ago, Johnoaudia6 said:

Hey - did the replaced battery solve the issue in the end? Got the same crazy problem on my A6 2015…

 

Thanks!

Hey man, sorry to hear that.  Issue isn't battery, it's just when someone sits in the middle of the back seat, so has to be something like a short somewhere.  In the end I just put the armrest down in the back so nobody can sit in the middle .... doesn't happen anymore since I did that.  Not a solution but it's good enough to keep my sanity

[Johnoaudia6]

Ah ok thanks! It happens in mine when I turn the steering wheel at low speeds ie when parking! 
 

more recently happening all the time.. reluctant to take to Audi as they’ll charge a fortune and likely just do trial and error and not sure if a kwik fit type of garage will have any idea on how to solve it…

any other suggestions from anyone I’d be most grateful for!

 

thanks

[BlackAudi]

Hey guys,

my 2016 c7.5 had been suffering the same crazy ‘Christmas lights’ symptoms for more than a year. Changed 3 speed sensors, steering column (had free play anyway) yet it persisted.

Finally decided to try changing speed sensors cables (dame there’s lots of stripping works😅) and it’s all good now.