GerryAZ wrote: Therefore, you need to connect a booster battery to the 12-volt battery under the hood.
When I first had to jump the leaf, I thought this was the case. However the Leaf would not respond. Turns out, the positive jumper cable needs to be connected to the +ve terminal but the negative jumper cable must be connected to the leaf ground (not the -ve battery terminal). It threw a code and would not start with the negative connected to the battery -ve, however booted up fine once connected to the leaf ground.