To diagnose an electrical fault - 12v

[Johnbot]

Hi all,

After using a 12v to usb adapter to charge a kindle and phone in the leisure battery 12v socket it stopped working. The power to the socket is gone, the fuse in the power supply unit is okay. Other systems work fine. Spoke to Sargent who made the EC400 power supply unit. They spoke in riddles, too quickly and like I had a background in electronics, so following two phone calls I have given up on them. They mentioned that it might be a connection issue in the cable but after tracing which one it was in the back of the ECU it doesn't seem to be getting power there either, or it starts at a couple of volts and drops away quickly.

Bar take it to a shop and potentially get taken for a ride does anyone have any ideas?

Thanks, John

 

[Alanedwin]

If the fuse is still good it sounds like a wire has burnt out or melted without the fuse going, which sounds unlikely. The current draw from a kindle is very low which makes it even more unlikely. I would suggest checking the continuity of all wires in case of a dry joint.

 

[TonyJones]

Do you know for sure that the polarity of your 12v supply at that point is right way round? Because USB adaptors are VERY susceptible to +/- issues.