FIXED! - Can you see why these USB ports aren't working? (Photos)

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
Hello.
I have an INNORI USB Automotive cigarette lighter power device that plugs into the cigarette lighter outlet in my car and is supposed to branch that into 3 cigarette lighter outlets and 2 standard USB outlets. Unfortunately, neither of the USB outlets work. Instead, when I plug a USP port power checker into the port, it will flash for a second then go VERY dim...as if it's not getting near enough power. Only a very faint glow.

Both ports do the exact same thing. However, the cigarette lighter ports work fine. Here are some photos and I'm wondering if anyone sees anything obvious? I checked the diode and it seems ok. The sky blue wire on the back is Negative 12v and the pinkish wire 12v +

I'm not really seeing any viable voltage step down for the USB ports. I'm familiar with buck boards and DC - DC power reduction somewhat and I don't see how this thing does the step down from 12v to 5v ?

Any advice appreciate.

INNORI_3.jpg
INNORI_1.jpg

INNORI_2.jpg
 
Last edited:

AlbertHall

Joined Jun 4, 2014
12,344
If you have suitable equipment you can check the diode, capacitor and inductor. If you an oscilloscope you could check the waveforms and voltages around the chip and compare to the datasheet. The chip is probably the prime suspect but that can only be a guess.
 

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
The diode seems ok. My VOM has a diode checker and I verified it does only allow current one way. Crude, but should signal it's ok?
I do have an oscilloscope, but Im thinking this is not worth the trouble to go through all that.

Seems I have this problem often with car USB power adapters. The lesson here is ALWAYS thoroughly test the USB ports when I get one...and send the stupid thing back immediately if it doesn't work.
 

AlbertHall

Joined Jun 4, 2014
12,344
The diode seems ok. My VOM has a diode checker and I verified it does only allow current one way. Crude, but should signal it's ok?
I do have an oscilloscope, but Im thinking this is not worth the trouble to go through all that.

Seems I have this problem often with car USB power adapters.
Cars are hostile to electronics - voltage transients, high and low temperatures - but you would expect that folk making things electronic would take all that into account but maybe they don't.
 

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
Welp,
I checked the voltages (and grounds) at the 4 USB pins and the grounds according to this USB pinout diagram....

usb2.png

Everything checked out. That leaves current as the problem.
Apparently there is voltage and ground...but very little current.
I checked that with my VOM and confirmed. .003milli-ohms when it should be somewhere between
1 and 2 AMPS (1000-2000mA)
I have no clue where that current is getting lost.
 

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
Just any case anyone else decides to try to help.....

Here's the pin out for the MC34063A
It is in fact a DC to DC Buck Converter so that's how I get the 5.15v at the USB port.
Still not sure why no current or VERY little.
I tested ground but I could use some help on how to possibly test the other pins
thanks

MC34063A.jpg
 
Last edited:

Thread Starter

Lumenosity

Joined Mar 1, 2017
614
SUCCESS REPORT !!!
Ok, for you hard core electronics whizzes this will be so mundane...but for me...an electronics novice (aka electrus noobis moronus), I'm stoked!!

I ordered a package of SOT-8 MC34063A chips from Texas. They arrived to day and I was able to successfully change out the chip and to my utter amazement... the darn thing now works perfectly! All functions and all usb ports working as designed.

So it was a gamble that paid. Man, it feels REALLY good to fix something and get it working again :)

INNORI_2.jpg INNORI_1.jpg
 
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