Hi 

I’m new to the forum so apologies if this has already been covered.

My Audi q7 2016 4m has recently started presenting ‘parking brake fault’ on the dashboard intermittently. I have plugged in my OBDII and identified the following codes: 

P056100

P056200

B154256

U105400

B163002

B131207

B122D29

B105413

B129B13

C118E00

I understand the majority relate to low voltage or open circuit and the last one relates to a potentially pressure issue in the brakes but I am unsure if this is just flagging up to to the low voltage issue. I have tested the battery and readings appear fine whilst engine is off, cranking and during engine running so I know the battery is fine. 
 

I wondered if anyone had experienced the same or could point me in a direction.

I understand it could potentially be a faulty voltage regulator ? But was also going to test the continuity of the fuses?
 

Any help appreciated.

Thanks  

47 minutes ago, Audi Q7 2016 said:

I have tested the battery and readings appear fine whilst engine is off, cranking and during engine running so I know the battery is fine. 

Please be specific about the readings you obtained. How old is the battery?

16 minutes ago, cliffcoggin said:

Please be specific about the readings you obtained. How old is the battery?

Hi, readings were 12.4 whilst engine off, 9.8 whilst cranking and 14.8 whilst engine running.

This evening I have also tested both sets of fuses and all appear fine.

purchased the vehicle 2 years ago so cannot confirm exact age of battery.

Thanks Al. The important one is the cranking voltage which seems to be OK, nevertheless I suggest you get the battery tested professionally tested to be certain, because a dying battery can lead to false warnings. If that proves to be fine a scan by a decent code reader should help locate the fault.

Apologies for jumping in on this, and particularly for the contra opinion, but 9.8v at cranking seems undesirably low to me. 
If it were mine, I would certainly doubt the battery’s efficiency on this c 10 year old car. 
As has been said on here so many times - get an Halfords store to test the battery’s % efficiency. If found to be sub standard then please come back to us before committing to buy, if you respect your wallet.

Regards,

Gareth. 

Thanks both appreciate the advice and comments. I will look into getting the battery tested. 

Please let us know the outcome.

PS If a new battery is needed ensure you get it coded to the car.

Cheers will do, booked in for Friday 👍

Checked out at Kwik fit n it appeared as replace battery. Ordered new battery and will fit it next week, after coding it in I will scan again for codes and see what if anything reappears.

Winter always reveals battery weakness.

Hi All, I’m going to be replacing the battery later this evening but I just wondered if I had to connect to a temp/jump start battery to save memory whilst replacing the main battery? Or is this not an issue, I will be coding in / registering the new battery once installed either way. Thanks in advance