Help with ABS, traction and EPB lights

[Asad]

Hi everyone Its Asad here, hope everyone is good. I am new to the forum (as in first post but been using the forum for a long time). I seem to have an issue with my ABS lights, EPB and traction lights on the dash. I have an Audi A6 C7 2012 s line 2.0d. They come on only on certain occasions and then somedays its not there. Sometime they last for 4 days then for 2 days they don't come on then its like on and off the whole days depending when I turn on/off the ignition. Now I have scanned this many times using different machines VCDS, Christa, OBD11 and it can't seem to actually pinpoint where the problem is. I have had the wiring checked for majority of the car, looking out for the looming, water, dirt damage and it seems fine. I have drove and did a live test and all speed sensor's are turning and moving at the correct speed. I keep getting generic codes like Function Limitation due to Missing Message. Its been on for a while and I cannot pass M.O.T with them on.  as of recently I scanned it again and on gateway I got a message saying control module incorrectly coded sensor electronic control module incorrectly coded but I have never changed anything on the car and I've had it for 2 years and this has only happened In the past 4 months. Has anybody experienced this problem before or can point me to the right direction. 

 

I appreciate this guys thanks 

Edited January 18, 2022 by Asad
updates info

[Asad]

Just to also add I have also checked the battery and it was showing as everything as fine. both ignition on and engine running. 

[Steve Q]

You've done a great amount of diagnostic work already which is great. It could be a failing abs module, especially if it's flagging up as an issue on the diagnostic check or failing abs sensors

[Asad]

Hi thanks for the reply. How would I know if its the ABS module that's failing it doesn't quite pin point it. I did a further scan with a Christa app and I got some random faults today I added as attachment. never had these before. Been driving fine since yesterday and today morning with no lights on dash and they all came back on again but what also came on today was the red steering light and a message please don't drive steering defective and constant beeping but the steering did not get heavy at all it was normal. I kept fully locking the tyres both ways and the light went and then came back again. did another scan and came back with power steering control module no signal/communication obd11 code 01309. but again it goes and comes back throughout the day. 

 

 

[Stevey Y]

9 minutes ago, Asad said:

Hi thanks for the reply. How would I know if its the ABS module that's failing it doesn't quite pin point it. I did a further scan with a Christa app and I got some random faults today I added as attachment. never had these before. Been driving fine since yesterday and today morning with no lights on dash and they all came back on again but what also came on today was the red steering light and a message please don't drive steering defective and constant beeping but the steering did not get heavy at all it was normal. I kept fully locking the tyres both ways and the light went and then came back again. did another scan and came back with power steering control module no signal/communication obd11 code 01309. but again it goes and comes back throughout the day. 

 

 

Hi I hate to say this but most of your faults would lead back to the battery as when they go down hill it causes all sorts of weird and wonderful faults, if its the original battery it should have the year of the battery on the unit somewhere, if in doubt change the battery clear all faults and start again, see which faults reappear that will give you a good indication of what is realtime and what is caused by voltage draw being low, depending on your milage my pure guess is that the oxygen sensor is failing and your throttle body has excessive carbon this throws up ABS and traction control lights as both units are switched out when the engine is struggling to produce enough power as both these elements are a massive drain on engine power, I would stick with VCDS as it is a manufacturer specific software.

Steve.

[Asad]

Hi Thanks for the reply. I will have a look at the battery tomorrow and get back to you on that information. Regarding the battery if I replace it do I have to get an start stop one or would a normal battery be suffice? can anyone send me a link to which sensor is that I need and replacing as the engine diagram points to two sensors for oxygen. 

The milage has now hit 161k and regarding the throttle body I do not get idling, rough milage or drive everything has always been smooth to be honest and it always starts the first time. I guess I can get it opened up and cleaned and put it back in. 

Someone said to me it could be the rear parking break motor, wiring around it or the wheel bearing. Is that possible I don't hear any weird noises coming from the car from those places. 

[Magnet]

Hello Asad,

As Steve Y says - you must suspect the battery first, and get it professionally tested - Halfords will do this. If the battery is unserviceable, then yes, you must ( in caps) replace it with a stop/start AGM battery. Halfords sell batteries, but I always buy on line from specialists battery suppliers such as Tayna ( there are more - just Google it). I only buy Varta/ Bosch in their 5 year warranty range - don’t buy cheap batteries, ( paying high prices does not always guarantee quality!), but buy a good brand at the most competitive price from the specialists. 
Kind regards,

Gareth. 

 

[Entwood]

Although I agree the battery might be on its last legs .. given the recent cold weather, and the fact folks are not using cars as much, it "might" be worth giving the battery a proper 24 hour charge with a decent "smart charger" that does recovery mode and AGM battereis .. I use a Ctek MXS 5 and do a "top up" charge if the car is not used for 14 days ....seems to stop most problems.

Worth a try before shelling out on a new battery ??

 

https://www.ctek.com/uk/battery-chargers-12v-24v/mxs-5-0-uk

[Magnet]

Many thanks Nigel.

Good point, and in any case, the battery should be charged - as best it can be - before testing. 
All modern stop/start vehicles are super sensitive to overall ( in caps) battery condition and the car’s battery condition monitor assesses all important parameters, so my view is that if the battery proves to be completely serviceable under a sophisticate test then happy days. If any monitored parameter shows marginal, then it would be new battery for me - sooner than later. 
I understand the CTec are great if the car is left unused for extended periods of time. However, they can be expensive  to the tune of a similar price to a new battery. What I’m trying to say is (in a not very clear way!) - it would not be economical to buy one, in the hope that it will revive an ailing battery. 
Kind regards,

Gareth. 
p.s. a new battery is likely to need to be recoded to the car. 

[Stevey Y]

Hi Halfords do an AGM battery for £200 and will code and fit it for another £25.00, in this weather its a no brainer and gets my vote with a five year guarantee, cheap fix if you cant code it yourself.

Steve.

[Asad]

Thanks for all the reply guys I appreciate it. I did do a battery check myself with a voltmeter and it did seem fine but I will get it professionally done to see if they can find anything with it. Will get in contact with Halfords and take it for a test. Will update you guys one done. 

 

Thanks 

[Magnet]

Hello Asad,

Sounds good. A simple battery test with a voltmeter is virtually meaningless. 
Apologies for a different of point of view, but £200 for an AGM battery ( of course dependent on size) would not automatically seem to be a no brainier to me. I would certainly consider it worthwhile to compare prices at online battery specialists before offending my wallet. 
Kind regards,

Gareth. 

[a6blacked007]

On 1/21/2022 at 10:00 PM, Asad said:

Thanks for all the reply guys I appreciate it. I did do a battery check myself with a voltmeter and it did seem fine but I will get it professionally done to see if they can find anything with it. Will get in contact with Halfords and take it for a test. Will update you guys one done. 

 

Thanks 

Update please @Asad

[a6blacked007]

Spoken with @Asad and he replaced 

Scanned with Odis which showed him fault.

AUDI A6 C7 2012 ACCELERATION YAW RATE SENSOR CONTROL MODULE 4G0907637

 Solved his problems 

 

Had look under gearstick ashtray etc can't locate sensor .

[a6blacked007]

@anthonywalker198734