Question about setting up battery charger for ISTA flashing

Maxwagen · 10-23-2023, 07:47 AM

I'm preparing to flash with ISTA+ to solve a glitching iDrive issue, and I have an old DieHard battery charger that I was planning on using. Is it best to set the charger to "50A engine start" mode for flashing? The other options are just 10A fast charge, and 2A slow charge.

fe7565 · 10-25-2023, 11:09 PM

Quote:

Originally Posted by Maxwagen

I'm preparing to flash with ISTA+ to solve a glitching iDrive issue, and I have an old DieHard battery charger that I was planning on using. Is it best to set the charger to "50A engine start" mode for flashing? The other options are just 10A fast charge, and 2A slow charge.

BMW says you need 85A continuous supply.

The car draws about 8A just sitting there engine/ignition off. It will probably use about 20-30 Amps and peaks of 30-40A during the upgrade process. The HU ECU itself takes about 1 hour (30-45min). You could idle the engine for that long to provide power. The battery charger you described will be a risk even with a new battery.

There are $12-20 used server power supplies (EBay) of 80A-100A, that you can easily convert with one resistor to 14V from 12V. There are many internet posts on that.

Billfitz · 10-26-2023, 07:34 AM

That 85A includes the available current from the battery. The purpose of a charger is to prevent the process from draining the battery to the point that the flashing process is curtailed.

Jimmert · 10-26-2023, 02:19 PM

I think BMW exaggerates the 80Amp a bit. A 50 Amp should do the job (so put it to that mode). I’ve flashed my car as well, and the max I’ve seen was 30 Amps. Just a tip, make sure the battery is fully topped up before you start.

yammagamma · 02-01-2024, 04:30 PM

Hi Jimmert

i see you use a vcx-se and had trouble when you entered programming with ISTA
im having the same problems, it works ok in diagnostics but when i enter programming
ista comes up with a error saying faulty interface or connection

how did you sort it out if you dont mind helping me
im using ista +4.39.20

10-23-2023, 07:47 AM	#1
Maxwagen Private First Class 25 Rep 127 Posts Drives: 2017 330i Wagon Join Date: Jul 2017 Location: Trumbull, CT iTrader: (0)	Question about setting up battery charger for ISTA flashing I'm preparing to flash with ISTA+ to solve a glitching iDrive issue, and I have an old DieHard battery charger that I was planning on using. Is it best to set the charger to "50A engine start" mode for flashing? The other options are just 10A fast charge, and 2A slow charge. __________________ 2017 330i Wagon \| Glacier Silver/Black/Anthracite, M-sport, Nav, Tech, Premium, DA, DA+, Cold, LED's, Carplay
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10-26-2023, 07:34 AM	#3
Billfitz Lieutenant General 8245 Rep 16,083 Posts Drives: '15 328iX GT Join Date: Jan 2015 Location: New Hampshire iTrader: (0)	That 85A includes the available current from the battery. The purpose of a charger is to prevent the process from draining the battery to the point that the flashing process is curtailed.
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10-26-2023, 02:19 PM	#4
Jimmert Private First Class 68 Rep 160 Posts Drives: BMW 420i F36 Join Date: Aug 2018 Location: The Netherlands iTrader: (0)	I think BMW exaggerates the 80Amp a bit. A 50 Amp should do the job (so put it to that mode). I’ve flashed my car as well, and the max I’ve seen was 30 Amps. Just a tip, make sure the battery is fully topped up before you start.
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02-01-2024, 04:30 PM	#5
yammagamma New Member 2 Rep 6 Posts Drives: f11 lci Join Date: Nov 2023 Location: ireland iTrader: (0)	Hi Jimmert i see you use a vcx-se and had trouble when you entered programming with ISTA im having the same problems, it works ok in diagnostics but when i enter programming ista comes up with a error saying faulty interface or connection how did you sort it out if you dont mind helping me im using ista +4.39.20
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