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Hi all,
Today had a Vw golf mk7 come in with a faulty 12v socket. The fault was that with a USB charger/adapter plugged in after 10/15 seconds the cable melted and several adapters melted too.
I decided to check quickly the amp draw which were approx 200-300 milliamps (not charging but lighting the little led on the adapter) then spiked to over 20 amps. Socket is controlled by the bcm.
Just wondering if anyone had a similar situation as I work in an independent garage that really doesn't allow enough time to diagnose anything properly and do not want to call a bcm to early.
That's a new one to me! :ohmy: Do you happen to have a diagram of this 12V socket. BCM controlled power outlets are new to me, too.
I'd be interested to know if there's a load you can apply to the socket that doesn't result in things cooking. Like, a small lightbulb on jumper wires? Hoping to distinguish between a wiring/BCM problem, and a problem with the adapters getting used.
Unfortunately I do not, I did have all the factory diagnostic tools and diagrams Vw use but my personal Odis/Vag laptop died on me last week. All the aftermarket technical data we get here in the uk are pretty rubbish and are never up to date (only have the a/c circuit diagrams for this vehicle).
The circuit seems pretty simple and only splices off to a second outlet in the boot/trunk.
I didn't even get to use the socket as within 15 seconds it had melted my charger cable that I plugged in just to check how quick it would happen as the customers adapter and lead had fully melted.
Really need some decent aftermarket resources here without breaking the bank.
A 12V socket puts out12V, the load plugged into the socket determines the current drawn. The socket should be fused, most I have seen are fused at 10A. A USB charger/adapter draws only a small amount of current, it should not be enough to melt anything. If there is a bad electrical connection at to socket it could cause heat to be generated as current is drawn, but there is so little current with a USB adapter that is not likely the problem. A mechanical defect in the socket that causes a partial short in the socket could enough heat to melt a the plastic housing of an adapter.
I've been reading this one in my e-mails, why isn't this thing blowing a fuse?!?
I was thinking along the same lines as Andy, Jeff and Ben. I also like Tyler's idea about varying the loads.
It probably doesn't matter, but is this socket also a cigarette lighter? Nothing dropped/poured down inside?
Man, that's a scary one :pinch:
"Ground cannot be checked with a 10mm socket"
Last edit: 8 years 4 months ago by Noah. Reason: thought of some questions...
Some of these far eastern made plug-in adaptors are scary low quality over here in the UK the consumer protection agencies keep warning people about them.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
sorry guys not been able to login for sometime..
It were fused with a 20amp standard fuse and it had popped several fuses, i noticed it were only causing the burning and spikes when cables were inserted into the 2.1amp usb socket of the adapter (it didn't pop fuses all the time). The 12v power outlet itself were in mint condition and looked brand new.
My first initial thought it were the adapters being used were a cheap brand which it did turn out to be the case. After i found a spare one from my dealership days and checked the current draw all were ok. charged a laptop without any issues lol.
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