Car won't start, headlights on? (Normal?)

Hi.

Is it normal for a car to not start after being left with the headlights on for 11 hours?

I have LED tail lights (2 W5W bulbs) and 15% amber turn signals in the front.
Theoretically, the 74Ah battery should be able to handle it, but a cold start for a TDI engine also requires a certain amount of reserve power.

m;

That might be possible.

I'm not sure what exactly is powered on in your car when "only" the parking light is on. It's quite possible that the onboard voltage control unit is no longer going into standby mode. And that can draw several amps .
The statement "15% blinker" alone makes me suspect that it's being controlled by the on-board voltage regulator. That would draw a significant amount of power.

Sure, I'll handle the coding for the 15% within the BNSTG.

I can measure the "idle" current later; then I'll know for sure.
I hadn't expected the BNSTG, and I also hadn't anticipated so much power.

m;

It is not possible to calculate how much remaining capacity the starter motor has before it no longer spins fast enough, nor how much power is lost due to the cold.

dieselmartin wrote:

... I hadn't expected the BNSTG, and I also hadn't anticipated so much power.

I didn't have that problem with the forester either... After 5 hours with the door open, the little Japanese car wouldn't start.
Door open -> 2.5A ... thanks a lot.