if its not the battery the line contactor is probably not closing all the way or tips are bad. to check it remove the right side cover, turn the key on and reach in and push the contactor...if it moves and locks in you could have a cpu problem, it pulls in at battery voltage then drops to a much lower voltage to hold. if it misses the first part of that process it wont pull in tight. if it doesnt move replace the contact tips. if it does.....get your wallet off of it's leash. i can give you some options if you are handy with soldering iron and pc perf board.

30-1 traveling AC driver 1 voltage low
30-2 traveling AC driver 2 voltage low
30-3 Material handling AC driver low voltage
Check fuse 1 and P3 cable but it sounds like johnr is right you probably got a bad battery
Hope this helps

Can't help you with the meaning of the codes. But you stated "Lift operates then cuts out." This might just suggest the battery is low on charge and the unit is in the lift interrupt mode typically the battery has been discharged 80%.
Put the battery on charge over night & see what happens. If it still acts the same measure voltage of the battery if an 18 cell battery (nominally 36 v) you should get a reading of about 39 to 40 volts across the battery.