Question about amperage on USB port in Console

[Mischik]

Hi everyone,
I just picked up my new F80 M3 yesterday. I'm wondering what the amperage is on the USB port that is in the center console. Is it the traditional crappy one amp or is it something better this time?
I have two E90 M3's and one E46 M3.

Looking forward to getting to know everyone here!

Dani

[sA x sKy]

It's way better than the old E series. It actually charges my iPhone much quicker and is comparable to a cigarette lighter charger that is 2.1 amps.

[sandwi54]

It's the high amp rating of 2.1A, and charges phones at a fast speed like a cigarette charger.

[Mischik]

Originally Posted by sandwi54

It's the high amp rating of 2.1A, and charges phones at a fast speed like a cigarette charger.

Thanks - I was told its 1amp - which would suck!

[sandwi54]

Originally Posted by Mischik

Thanks - I was told its 1amp - which would suck!

I believe the old CIC navigation charged at 1A, but I'm pretty sure the NBT charges at 2A because mine charges lightning fast!

[Mischik]

Originally Posted by sandwi54

I believe the old CIC navigation charged at 1A, but I'm pretty sure the NBT charges at 2A because mine charges lightning fast!

What can I use to confirm?

[sandwi54]

Originally Posted by Mischik

What can I use to confirm?

I guess one way to confirm is to compare the charging speed between a 2.1A cigarette light charger and NBT's.

[SakhirM4]

Originally Posted by Mischik

What can I use to confirm?

Check the owners manual

[sergkoko]

Look up the pinout on a USB cable, you will have a negative, two data wires and power wire, take a DMM and measure the amperage, but you will need to hook up a load to it like a charging phone and place it inline with the ampere meter (any DMM should have this).

If it's a faster USB version it will just have more data wires that you can disregard, just measure the power wire, put negative probe on ground. If you want I can google you some pictures lol

Good Luck.

Edit: Here is a diagram, the car is the battery in this case and the light bulb is your phone (load).

[sandwi54]

Originally Posted by sergkoko

Look up the pinout on a USB cable, you will have a negative, two data wires and power wire, take a DMM and measure the amperage, but you will need to hook up a load to it like a charging phone and place it inline with the ampere meter (any DMM should have this).

If it's a faster USB version it will just have more data wires that you can disregard, just measure the power wire, put negative probe on ground. If you want I can google you some pictures lol

Good Luck.

Edit: Here is a diagram, the car is the battery in this case and the light bulb is your phone (load).

In general, what you described is the correct way of measuring the current. However, it's not easy to insert a DMM in series with the power or ground, unless the person puts a wire between male and female USB connectors. In addition, the phone may NOT always charge at the maximum current, depending on the state of the battery, and this is decided by the iPhone's internal battery charger.

The easiest way to check the charging capability is to probe the D+ and D- lines. There are three main USB charging protocols: DCP, CDP, and Apple's proprietary charging. To make things less complicated, the way a USB host determines which standard the USB device can support is by applying a voltage to either D+ or D- (either 0.6V, 1.2V, 2.0V, or 2.7V), and see which one the USB device responds to (by pulling the other data line low). The 1.2V case is for the fast 2A charging scheme and one can simply probe both the D+ and D- lines on an oscilloscope to see if the car's USB host pulls the data line to 1.2V. I could do this but I am too lazy to drag an oscilloscope home from work. All I need to know is that my phone charges fast

[sergkoko]

Very cool i did not know that, it would be pretty sweet to have an o-scope at home

[Mischik]

Originally Posted by sergkoko

Look up the pinout on a USB cable, you will have a negative, two data wires and power wire, take a DMM and measure the amperage, but you will need to hook up a load to it like a charging phone and place it inline with the ampere meter (any DMM should have this).

If it's a faster USB version it will just have more data wires that you can disregard, just measure the power wire, put negative probe on ground. If you want I can google you some pictures lol

Good Luck.

Edit: Here is a diagram, the car is the battery in this case and the light bulb is your phone (load).

Thank you!