Self-Study Program

21
Battery change history
The data from the previous 3 battery changes is stored in the battery change history.
The entry in the history data is made when the battery energy management system is encoded.
Therefore, it is very important that the energy management control unit J644 only be encoded when a new
battery has actually been fitted. Encoding deletes all history data. In this case, it will not be possible to
perform, among other things, a reliable battery test using the VAS 5051, because this test utilises the history
data. Likewise, it will be very difficult for Audi AG to comment upon queries submitted through DISS, because
the history data is no longer available or is falsified.
Display on tester
The battery change history contains no more than 3 lines of data.
Additional data
The following information can be read out with the "Additional data" button:
– Energy balance of the previous 5 trips
– Energy balance of the previous 5 standstill periods
– Time programming in the dash panel insert
An evaluation of the data produced the following results:
Original battery serial number:
1401270070
2005-06-24, 12:03:17 time and date of removal of the battery.
-00050 Ah, energy balance of the removed battery
-240 Ah, energy throughput of the removed battery
Energy balance of the previous 5 trips
The energy balance and the duration of the previous 5 trips are recorded.
Display on tester
Negative energy balances mean that the battery was discharged during the trip!
Causes:
– driving short distances
– many electrical consumers
– low battery charge
In Audi vehicles, the alternators are always designed in such a way that discharge of the battery while driving
can only occur in very unfavourable operating situations. This means that the alternator must be tested for
proper function if the energy balance is negative for a prolonged period of time.
Energy balance of the previous 5 trips =
+003.5 Ah, energy balance, trip duration in hours 000.7
+010.3 Ah, energy balance, trip duration in hours 002.3
+008.2 Ah, energy balance, trip duration in hours 001.2
+003.5 Ah, energy balance, trip duration in hours 000.5
+001.3 Ah, energy balance, trip duration in hours 001.2