Car does not find new CAC after battery exchange - help please!

[Holger]

hello experts,

in october 2017 i had a battery exchange on my 2.0 roadster "signature 250" , built in 2010. by occasion i got a fine used one with 149 Ah CAC. my old finallly had 129 Ah only. till now after months and 2000 miles with the better battery the car still has not accepted the new CAC and extended range (~ 285 km /174 miles expected) but still shows 129 Ah and my old ideal range of only around 254 km/157 miles.

the service center once told me the car would "learn" to accept the new range/CAC what could last couple of charging cycles and many dirven miles, but since battery exchange till now NOTHING AT ALL has happened. i did several resets of the SOC in the service menue but i did not help either.
the service center has offered a complete update to make the car sensible for the alien battery.

do you have an idea how i could manage that problem by myself? the service center is loacated 150 miles away from my home...

Holger

 

[dhrivnak]

Have you done a long drive where you go from 100% to 5% (or lower) on the battery. I hear one occasionally needs a full charge discharge for the electronics to calibrate.

 

[Holger]

hmm...i am not sure whether i did. i think it was more than 5% left.
but which 100% do you mean? 100% total full battery = end of range or performance charging? or 100% standard charging/ideal range?

(also: 5% of total content/capacity or 5% rest of ideal range?).

i assume, you ment 100% possible maximum capacity and 5% away from total discharge.

i will test your suggestion next week (icy winter currently here ...), drive the car carefully down to "unknown range" alert and hook it on voltage then.

a buddy suggested to start a performance charging then with at home maximum possible current (32 A) so that the battery is not permanently cooled down and the battery cells are able to reach their maximum load.

any other thoughts or hints?

 

[supersnoop]

The advice is to do a range charge and then take a single long drive (one turn of the key, never shut off) until you hit the threshold where the car says it can't calculate the estimated mileage remaining. Then charge it back up with a standard charge. That should allow the car to calculate the CAC.

My car took about a year before the CAC climbed up to reflect the replacement battery's capacity. I probably made three trips like the one described above. It just takes a while for the car to learn the new battery. There's not a simple reset function.

 

[Holger]

thanx snoop,

i will try that procedure. moderate driving recommended or would it not matter how slowly or fast and furiously i run down the battery?

BTW: rather stupid, impractical electronic management/software. right?

 

[djp]

Another option is do a range charge and then let it sit in the garage for a day with the cabin heat running on full. You don't need to take the SOC down to "unknown range", the bottom 20% (in the red) is enough to trigger a recalculation.

 

[Holger]

i think i already drove down the battery from a full range charge under 20% - but it did definitely NOT trigger the recalculation...

 

[supersnoop]

i think i already drove down the battery from a full range charge under 20% - but it did definitely NOT trigger the recalculation...

It won’t happen all at once. The car has to learn the new battery, and it learns slowly.

 

[Holger]

It won’t happen all at once. The car has to learn the new battery, and it learns slowly

pretty stupid pupil imo...

 

[Holger]

i think i already drove down the battery from a full range charge under 20% - but it did definitely NOT trigger the recalculation...

...but i am afraid it had not been not that essential "one turn of the key, never shut off"-trip.

so i will try again...

 

[Holger]

The advice is to do a range charge and then take a single long drive (one turn of the key, never shut off) until you hit the threshold where the car says it can't calculate the estimated mileage remaining. Then charge it back up with a standard charge. That should allow the car to calculate the CAC.

leaving the car in P-position in between (for instance for peeing...) would be ok, right?

 

[supersnoop]

leaving the car in P-position in between (for instance for peeing...) would be ok, right?

On the 1.5, then only way to P is to turn it off. Maybe that’s different on the 2.x?

 

[Holger]

yes, different. 2.0 is definitely ON in position P and key stays untouched in ON position in the starter lock too.

 

[Holger]

The advice is to do a range charge and then take a single long drive (one turn of the key, never shut off) until you hit the threshold where the car says it can't calculate the estimated mileage remaining. Then charge it back up with a standard charge. That should allow the car to calculate the CAC.

made that procedure yesterday but IT DID NOT WORK!

 

[supersnoop]

made that procedure yesterday but IT DID NOT WORK!

Did the CAC climb at all? As I said above, it will take time. It took my car about a year to figure out the true CAC after the battery was replaced; from ~142 to 156.

 

[Holger]

yes, it did! the old battery showed <129 Ah. today i found 130,70 Ah on the screen.

 

[X.l.r.8]

I’m not sure that is considered an actual increase. How did you confirm the actual CAC of the donor pack. Also has your mileage (projected or actual) increased

 

[Holger]

132,22 Ah today...