So a while back I put a USB in the center console and just tapped power from the power seats, under the assumption that the power was off when the vehicle was off (which seemed to be true at the time).
Now it seems to be keeping the seat circuit live all the time and the USB is draining the battery.
Well, not all the time, just when it's in the mood.

Anyone have any idea's about this?
ECU just making up the rules as it goes along?

Best laid plans and all.

 

Wait, it's supposed to be 45 seconds. Maybe something else is draining my battery. Sigh.

 

Yep, I was wrong. Hard to test as it's linked to the driver's door.
I just found out there's only one key hole on these things. Would have thought I'd notice that before.

Now what else drains batteries on these things?

 

I'm not familiar with circuit design on the heated seats. It may depend on how the USB is connected. For instance, if the heater circuit is ground side switched and it's somehow finding a ground through the USB wiring. It may not be enough of a connection to turn the heater on, but could certainly put a draw on your battery. Does the USB port work with the heated seats in the ON position? This is very important. If it does not work with the heater in the seats ON, then you're on the ground side of the heated seat circuit. Which is a little tricky because both power and ground side will have 12v until the heater is turned on.

 

To my knowledge the power seats and windows will operate for a short time after the engine is switched off, I would guess about 30 to 60 seconds so, as already stated, maybe the USB is causing a false draining circuit somehow. However, any additional electrical connection is better taken directly from the ignition switched positive circuit to avoid any spurious battery draining. I'm by no means an electrical whizz kid particularly on auto electrics as they are very different to ordinary circuits.

 

I'm the complete opposite! Gimme 14v DC all day long, I'm good. Ask me to wire a light switch in a house and I'm completely lost...why is there three wires?!

 

Radio is switched on and off.
Tap the cold end of the RADIO fuse in the fuse panel.

 

Just to clearify: Power is pulled from the seat mechanical power not the heated seats. It's a big circuit (30 amp) so my little USB is nothing to it.
Now that I know that circuit goes down after 45 seconds I'm back to being pleased with it.

I really should just break down and put a new battery. The current one tests as "ok", but was not a great battery to begin with. Just a whatever fits battery the last guy put in.