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35is Battery Replace
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Onlinetiglon
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35is Battery Replace
I've suspected I need a new battery for a while, a couple of times when the car has gone in for work they've said the battery was low and have put it on to charge, and it's been on trickle charger for the past couple of months but never gets up to 80%.
On Friday after updating the map with MHD, the warning late came on for hill start not working - I'm guessing it's due to the battery, is that something that will clear once I change the battery, or will I need a software update?
New Bosch battery is on its way (only £140 from batterygroup.co.uk as opposed to £270 from Eurocarparts etc, for identical battery!) and is the same spec as the original BMW labelled battery, 760a 70ah. Am I right in thinking that it will only need registering, which I can do with MHD, and not coding?
On Friday after updating the map with MHD, the warning late came on for hill start not working - I'm guessing it's due to the battery, is that something that will clear once I change the battery, or will I need a software update?
New Bosch battery is on its way (only £140 from batterygroup.co.uk as opposed to £270 from Eurocarparts etc, for identical battery!) and is the same spec as the original BMW labelled battery, 760a 70ah. Am I right in thinking that it will only need registering, which I can do with MHD, and not coding?
2014 E89 35is Valencia Orange 788M wheels (M2 Competition), E90 M3 control arms, Eibach Pro Kit Springs, MHD Stage 1
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- Lifer
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35is Battery Replace
Hill start is a DCS function releasing the normal brakes not parking brake…once a battery is low all sorts of s**t can happen..
MHD doesn’t do registering…you’ll need a Protool, Carly type product or a bespoke OBD programmer like Foxwell..
MHD doesn’t do registering…you’ll need a Protool, Carly type product or a bespoke OBD programmer like Foxwell..
Modded E89 20i MSport 2017-2022…Even more modded E89 35is 2021 onwards..details here.. https://www.dropbox.com/s/8h1vabklgzf4v ... t.pdf?dl=0

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Onlinetiglon
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35is Battery Replace
On the "codes" tab, under "reset adaptations" there's an option for registering the battery.
2014 E89 35is Valencia Orange 788M wheels (M2 Competition), E90 M3 control arms, Eibach Pro Kit Springs, MHD Stage 1
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- Lifer
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35is Battery Replace
Well I just checked..you are right

Must have added that in since I first looked..
MHD just gets keeping better ..
Modded E89 20i MSport 2017-2022…Even more modded E89 35is 2021 onwards..details here.. https://www.dropbox.com/s/8h1vabklgzf4v ... t.pdf?dl=0

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Onlinetiglon
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35is Battery Replace
Yeah they've added a few things since I last checked. For N54 there's now antilag, switchable maps (I think just for different fuel types, rather than different stages or other settings, unfortunately) and a few other random bits I'd never heard of.
2014 E89 35is Valencia Orange 788M wheels (M2 Competition), E90 M3 control arms, Eibach Pro Kit Springs, MHD Stage 1
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Online
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35is Battery Replace
I'm surprised the 35is doesn't have the 80AHr battery.
When i inquired about adding software for servotronic which i assume all 35is have as std. i was told needed to upgrade the alternator and battery to 80AHr.
I was looking to improve the steering feel.
When i inquired about adding software for servotronic which i assume all 35is have as std. i was told needed to upgrade the alternator and battery to 80AHr.
I was looking to improve the steering feel.
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35is Battery Replace
I can never work out the logic on the 70ah vs 80ah fitment..
My 35is had 70ah as standard..I did put an 80 ah in.
FWIW the E89 uses special current management logic to ensure the EPS always has enough power come what may..so battery capacity in this case is not directly relevant…unless your alternator fails..
My 35is had 70ah as standard..I did put an 80 ah in.
FWIW the E89 uses special current management logic to ensure the EPS always has enough power come what may..so battery capacity in this case is not directly relevant…unless your alternator fails..
Modded E89 20i MSport 2017-2022…Even more modded E89 35is 2021 onwards..details here.. https://www.dropbox.com/s/8h1vabklgzf4v ... t.pdf?dl=0

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Online
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35is Battery Replace
An 80Ah should deliver the power for a bit longer, but that wouldn't matter once the engine is running.
It might have a higher CCA, which could be what is being recommended, and it's just a coincidence that the Ah is higher?
I wouldn't have thought the extra electronics etc. would make any real difference to the power draw. A 6 might be harder
to crank than a 4 perhaps?
For comparison, my other car is a diesel, which has a higher Ah/CCA battery than the petrol equivalent (and it needs to be AGM since
it has stop-start)
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35is Battery Replace
I’ve looked at many VINs that have been decoded and failed to see the causal link between options and battery size..given the alternator is rated at 230 amps once the engine is running you’ve got 2.5 kwatts of juice..Kevin wrote: ↑Mon Mar 20, 2023 4:56 pmAn 80Ah should deliver the power for a bit longer, but that wouldn't matter once the engine is running.
It might have a higher CCA, which could be what is being recommended, and it's just a coincidence that the Ah is higher?
I wouldn't have thought the extra electronics etc. would make any real difference to the power draw. A 6 might be harder
to crank than a 4 perhaps?
For comparison, my other car is a diesel, which has a higher Ah/CCA battery than the petrol equivalent (and it needs to be AGM since
it has stop-start)
The main pros for a bigger battery are longer time to allow car draining it’s electrics on standby, better chance of start in ultra low temps, more reserve capacity for regenerative braking..listen to sound system longer without engine running , plus extended use of blow by heating..
Modded E89 20i MSport 2017-2022…Even more modded E89 35is 2021 onwards..details here.. https://www.dropbox.com/s/8h1vabklgzf4v ... t.pdf?dl=0

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Onlinetiglon
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35is Battery Replace
FYI, the battery registration function on MHD hasn't worked for me. "Failed" every time. Maybe I should read the manual....
2014 E89 35is Valencia Orange 788M wheels (M2 Competition), E90 M3 control arms, Eibach Pro Kit Springs, MHD Stage 1