Philc98

What is the importance of coding the battery?

New to A8s

MP4.2+6.0

The car uses it to calibrate electrical capacity and consumption in the power management system. It looks at things like battery aging, estimated reserve capacity, etc. On a pedestrian basis it puts up that display on the MMI screen, but more importantly it makes decisions about when to start shedding optional load. Thus at 50% it starts cutting very optional stuff like keyless entry, rear fridge on W12, etc. Remote access goes later. MMI screen also gets cut eventually. There are long lists of cut items from 50% in steps down to 10% if you dig into it. At 10% it is just trying to to keep the car alive at least enough to start, so it is whacking anything left that is non core critical to start or drive.

I have left the lights on (manual setting, no "A") once or twice and then into the night at work a few times. Like 12 hours, albeit only parking once key is off. With a decent battery it can be the difference between a still good start and having to call the emergency service or get the cables out and look for a friendly jump, plus it can help save battery from the destruction that tends to accompany full discharge scenarios.

Having said all that, there are a fair number of anecdotal reports the car figures out it has a fresh battery after a while anyway even with new coding and assuming it is the same size/new capacity spec. Makes sense since system reads battery parameters, and unless it only adjusts in one direction (down), it should be able to use the same algorithms to deduce when battery gets "healthier" too.

cyrus89

I have a problem again, I have a new battery, I have driven like a 2 month now, everything worked fine until this morning, starter just wont crank, battery is drained low again to 11.96, alternator works fine. I dont get it, weather is warm all the time. There should be another problem like battery energy management? got vcds

cyrus89

is this causing the trouble?

Address 07: Control Head Labels: 4E0-910-7xx-07.lbl
Part No SW: 4E0 910 769 Q HW: 4E0 035 729 A
Component: Interfacebox H43 5570
Revision: 00000000 Serial number: 300II027509452
Coding: 0000002
Shop #: WSC 00000 000 08192
VCID: 3A7BD46375AA42CE9A7-806F

Subsystem 1 - Part No: 4E0 910 609
Component: Bedienteil MMI H41 0010

Subsystem 2 - Serial number: 317AH037508109

Subsystem 3 - Serial number: ˙˙10.01.03˙˙˙˙˙˙˙˙˙˙˙˙˙˙˙˙˙

Subsystem 4 - Serial number: ˙˙˙˙˙˙˙

3 Faults Found:
00003 - Control Module
005 - No or Incorrect Basic Setting / Adaptation
Freeze Frame:
Fault Status: 01100101
Fault Priority: 5
Fault Frequency: 1
Reset counter: 0
Mileage: 271300 km
Time Indication: 0
Date: 2003.02.27
Time: 00:11:17

02003 - Driver Identification Control Module (J589)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 5
Fault Frequency: 1
Reset counter: 0
Mileage: 271300 km
Time Indication: 0
Date: 2003.02.27
Time: 00:11:27

02244 - Button in Control Head is Stuck
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 5
Fault Frequency: 1
Reset counter: 40
Mileage: 271300 km
Time Indication: 0
Date: 2003.02.27
Time: 14:03:38

Freeze Frame:
Bin. Bits: 01000000
Bin. Bits: 0000000
Bin. Bits: 000

Mister Bally

As the sticky

https://www.audiworld.com/forums/a8-...-read-2877219/

mentions; use the search function as there are dozens of posts discussing battery drainage. Also mentioned is that standard automotive troubleshooting techniques need to be used from time to time when diagnostic scans provide undefined results. Here, use a current draw meter to verify current consuming devices when the car is shut down. Or, recode the battery. Or, let the car sit for 6-8 hours and then put your hand on the alternator. Is it warm? if so, it is defective. Actually, a diode is leaky and has latched in a shorted mode and must be replaced. Again, standard automotive troubleshooting techniques are sometimes necessary.

There are hundreds of posts in the D3 forum that mention clearing codes (after saving them for reference) and see if they reappear. Sometimes they can be old codes. Not sure if yours are really twelve+ years old or did they take place with the vehicle's clock reset due to a drained battery. Only you can verify.

ltooz_a6_a8_q7

After market components if you have any. All electronic components in the A8 (original components) have a power sensor wire, which will shut the component down after the ignition is off to save energy because they're all hot wired. After market components may not have the feature of shutting down after so many minutes and drain your battery. If you park the car in the garage, don't lock the doors. Truly, I don't really believe that coding the battery helps anything, the problem will always be there until you find the root cause of the drained battery.
Check to make sure your alternator is actually charging, if the engine is on, measure across the + to ground post should be 14V+. If the alternator is charging, then it's just the battery to hold the charge and something is draining it while sitting with engine off.
I always park my cars in the garage, unlocked and the keys are in the cup holders, never had a battery problem ever with all my cars, Q7 is 08 until now, original battery, this 06 A8 also has original battery.
Find the real problems and this may be the one (check your MMI control buttons around the shifter):

02244 - Button in Control Head is Stuck
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 5
Fault Frequency: 1
Reset counter: 40
Mileage: 271300 km
Time Indication: 0
Date: 2003.02.27
Time: 14:03:38

Cheers and good luck,

Louis

cyrus89

codes are all new just the dates are wrong, but I charged the battery full, everything works fine but the starter wont turn. Is this possible that no power is transmitted to starter, because vcds give me 2 fault codes.
2 Faults Found:

18010 - Power Supply Terminal 30
P1602 - 002 - Voltage too Low - Intermittent
19510 - Starter Will Not Turn
P3054 - 001 - Jammed or Electrical Malfunction

Readiness: 0110 1101

Alexxelax

Check my solution, may work for you. here https://www.audiworld.com/forums/a8-...mlins-2880237/

cyrus89

are those 381 starter relays?

Jack88

Should be. According to this, there are two starter relays with that part number.
AUDI A8 [A8] (EUROPE) 2007: ELECTRICS: 93700. RELAY PLATE AND RELAYS