On Wed, 07 Dec 2016 22:24:44 +0000, Harry Bloomfield wrote:

David wrote :
Pin 9 is for battery charging and always on.

I am not familiar with the 13 pin, but the above would seem to be wrong.

If pin 9 is always on, that means that with a flat battery on the tow
vehicle, it will back feed from the trailer when any attempt is made to
crank the engine.

One the 7S the battery charge pin is only connected when the primary
battery is being charged, to avoid such problems.

AFAIK there is ECU protection which cuts the current if the vehicle
battery goes below a certain voltage.



--
AMD FX-6300 in GA-990X-Gaming SLI-CF running Windows 7 Pro x64

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus