|
|
|
|
|
|
BMW Garage | BMW Meets | Register | Today's Posts | Search |
|
BMW 3-Series (E90 E92) Forum
>
Adding usb charger in e90 center console.
|
|
07-09-2020, 05:08 AM | #1 |
Brigadier General
2887
Rep 4,333
Posts |
Adding usb charger in e90 center console.
Hi everyone.
I’ve been wanting to add a usb charger under my armrest where the aux goes for a while now. I have the stock single aux port currently. I also have a spare stock usb/aux block with the oem plug and harness. The harness for the usb has 4 wires. Is there anyway I can send power to 2 of those 4 wires to power that USB port? I don’t want to do the mod that allows the usb to work with audio/steering wheel controls. I just want the usb to power up and charge. I believe I saw a diy post/video last year of someone wiring it up for power last year. They didn’t mention which wires were power so I ended up frying a tablet. Thanks.
__________________
E90 335i-408WHP. Alpine over Terra brown
E70 X5 35i M Sport-Stage1 Tune. Alpine over Black E91 328 M Sport-Alpine over Black-Alpine over Saddle brown. E93 335i-DINAN tuned. Alpine over Saddle brown |
07-09-2020, 08:06 AM | #2 |
Colonel
1227
Rep 2,476
Posts |
The stock USB power source doesn't have enough current to charge modern mobile devices It'll barely maintain my Pixel, after a 1 hour drive without using my phone, battery percentage will only increase 1-2%.
My initial plan was to add a more powerful charger hidden under the console and tap into the cars USB jack wiring, but in the end I just plugged in a low profile cigarette lighter charger next to the USB/AUX jack. If you want to pursue this, pins 1 and 4 on the USB jack are power and ground. On the female USB jack on the car, looking directly at it with the pins on the bottom, pin 1 is far left(5v) and pin 4 is far right(ground). If the back of the jack you have it isn't clear as to which USB jack pin corresponds to which harness plug pin, you can easily use a digital multi meter to check continuity between pins. Keep in mind that if you're looking at the male cable end, with the same orientation with the pins on the bottom, pin 1 will be far right and pin 4 far left so when it faces the female jack the pins line up 1-1 and 4-4. |
Appreciate
0
|
07-12-2020, 05:05 PM | #4 | |
Brigadier General
2887
Rep 4,333
Posts |
Quote:
I just want it there to power the Bluetooth dongle to plug as into the aux right next to it. I could tap the cigarette lighter wires and pull power from there right? Thanks. |
|
Appreciate
0
|
07-12-2020, 05:48 PM | #5 |
Colonel
1227
Rep 2,476
Posts |
Yes, it should be enough for thE BT receiver as I used to have one powered by the factory USB. Didn't sound all that great as it still used the AUX jack for the input and that is a weak link as far as sound quality, but it worked.
Cig lighter power will be 12v, and USB power is 5v, so no, you can't directly tap the cig lighter wiring for USB power. You can, however, use the cig lighter wiring to power an actual USB charger which you can then wire to the factory USB jack. |
Appreciate
0
|
07-13-2020, 03:26 AM | #6 | |
Brigadier General
2887
Rep 4,333
Posts |
Quote:
Yea the BT receiver stiLl uses the aux but it’s really the cheapest option for audio I can think of. I don’t follow your last sentence. What type of usb charger would I need?
__________________
E90 335i-408WHP. Alpine over Terra brown
E70 X5 35i M Sport-Stage1 Tune. Alpine over Black E91 328 M Sport-Alpine over Black-Alpine over Saddle brown. E93 335i-DINAN tuned. Alpine over Saddle brown |
|
Appreciate
0
|
07-13-2020, 07:27 AM | #7 |
Colonel
1227
Rep 2,476
Posts |
If you tap the wiring for the cig lighter and go directly to the USB jack, you'll have 12v at the USB jack - this will fry whatever device you plug in to the USB jack because USB power is 5v.
In order to use the 12v cig lighter wiring, you need something to step down the 12v to 5v. A car charger designed to be plugged into a cig lighter outlet does just that, along with monitoring the current load based on battery charge level and reduces current to a trickle/maintain level once the battery reaches full charge. Taking one of these chargers apart and wiring it inline between the cig lighter wiring and the USB jack wiring and hiding it under the console gives you that 5v charging capability at the USB jack under the arm rest. Solder 2 wires for 12v positive and ground on the input side of the charger and connect those to the 12v cig lighter wiring. Solder 2 wires to the 5v positive and ground on the output side of the charger and connect those to the 5v USB jack wiring. |
Appreciate
0
|
07-13-2020, 01:59 PM | #9 | ||
Brigadier General
2887
Rep 4,333
Posts |
Quote:
Ok thank you. I get it now. I’m guessing I can’t cut the wire to the desired small length right? I’d have to take it apart from the very ends right? I will take one apart today and see what the inside looks like. Quote:
I added that already, although it’s never really used because no one sits back there. This may seem like a lot of hassle to some because I already have a charger right next to the aux, but even with a dual charger, it gets annoying if I have to charge 2 other things+the BT receiver. I have to decided if I want to unplug my phone or BT receiver to plug a third item. It would be easier if I just had the BT receiver plugged into the USB power on the aux block. It would also clean up the wiring under the armrest. Thanks. |
||
Appreciate
0
|
Bookmarks |
|
|