Thread: Is it ok to connect air compressor directly to battery?

Hmm..I might pick the bolt that the earth wire is attached to from the battery then...hopefully nothing blows up..thanks heaps guys ..the warning in the handbook re connecting 12v devices directly to the battery might cause sparks and explosion had me worried.. 8) ..hence the post ...

Originally Posted by mikehzz

Drivesave, why isn't it advisable to connect directly to the negative terminal? Connecting to the body near it would almost be the same thing I would assume. Just interested to know. Cheers.

Modern vehicles have a sensor in the negative lead which interfaces with the vehicles to ensure regulated charging.

Connecting directly to the battery screws this load monitoring and can cause problems.

Originally Posted by oznut

Hmm..I might pick the bolt that the earth wire is attached to from the battery then...hopefully nothing blows up..thanks heaps guys ..the warning in the handbook re connecting 12v devices directly to the battery might cause sparks and explosion had me worried.. 8) ..hence the post ...

Why not wire up a 50a Anderson up the front there... Will make life easier in the future!

Hi oznut and not using the negative terminal when jump starting is an international industry wide precaution for exactly what you suspected.

If a battery has been worked hard, like a flat cranking battery is when try to start a motor, it will gas and there is than the potential of an explosion.

Just look for a stud with a cluster of earth wires connected to it and your have your earth point.


Hi mikehzz and the earth lead on many new vehicles, including most new LRs, is used to monitor the state of the cranking battery.

If you place any loads on this cable, other than that of what the battery is going to create, you can cause erroneous readings of the battery which can lead to battery being under charged or over charged.

Thanks for the explanation drive safe...with the MY13 FL2, there is an earth strap coming from the negative terminal of the battery to a bolt next to the battery, would that bolt be ok to connect to? Please see picture by stownrow ..thanks

Freel2.com - View topic - Extra earth strap now fitted as standard