[keithhampson]

Hi I have just bought a renault laguna 2003 estate and was wanting to buy a 12v cooler/mini fridge for it for when I go fishing, is there anyway that I can keep it powered even when the key card is removed to keep it powered?

If I can keep the 12v socket powered on, how long could I run the mini fridge for before I completely drained the battery running the cool box, based on the the cooler using 48 watts.

Keith

 

[costeau]

Not sure if it's linked to the ignition, but I'll take a look at that tonight with my multimeter.
(I'm too lazy to check the owner's manual. { )

If it does power when ignition is off, how long depends entirely on the car's battery, and what its charge state is.
I wouldn't leave it plugged in overnight if I were you, but a couple of hours should be just fine.

 

[madnoel10]

It is very difficult to calculate how long you could leave the fridge connected as it will not run continually and will cut in and out depending on temperature.

You'll also need to know the output of the battery.

 

[lags04]

I think the OP already knows the power is only present with the ignition on (which it is).

I have a coolbox that has a low battery setting which I can only assume means it uses less power. But I personally wouldn't like to leave it if you could (without the ignition on) for more than about 30mins to be on the safe side.

 

[costeau]

Okay. If there's a need to mod this from ignition-dependent to permanent,
I'm not sure whether the trailer wiring for a towbar would carry a permanent +12V wire or not,
or if there are any other sources of permanent +12V in the boot area, and what amperage they may be carrying.

If you were to wire up for an additional battery (say for a subwoofer and amp rack),
perhaps add a fuse for the cooler, and wire the outlet to that instead?