i see this thread is old
but for future reference:

raymonds have a setting that determines the BSOC (battery state of charge)
it does this to determine if the same battery has been reconnected

if you take a battery off thats low on charge
and the next battery is less than 75% greater in charge then the BDI will not reset to the new battery's level
it will continue to read the old percentage (even though you did put a stronger battery on it)
75% is the default setting it can be lowered to 55%

so seeing you got 1 battery to 4% id imagine the others you have arent in the greatest of shape
this might explain why it didnt reset even with another battery

i had a cat do this a few weeks ago (some cats use the same software)
i had to lower the BSOD % in the menu to reset the BDI (ramond calls it the OD- operators display) with an older weaker battery

to access the menu and the analog potentiometer test
you have to know the superword

you say you have the book
if you look up test A03 it has how to test with a voltmeter
its easier if you know the superword though
most likely your pot is bad or out of adjustment
use the midpoint reading and look for smooth sweeps on you DVM as you move it foward and backwards
(key on dont step on the pedal, backprobe the connectors that they ID in the test)

have you relearned the throttle pot (vr1)?

Code 80 appear when the throttle controller reading is out of range. In neutral position the reading should be 2.0-3.0 V. Pl adjust it and your truck will be ready for operation. If you could not get the 2.0 - 3.0 V then Please change your VR1.

does the code#80 only happen in fwd tractio ?

chances are all the batteries your swapping are faulty, not fully charged or a bad connection/ low voltage problem from battery to truck.

My first thought is to buy something else :-)

Seriously though, make sure you check the battery voltage under load. Those units will do some funny things if the battery voltage drops below ~18V under load.
There is also a battery reset setting, if it's set too high then the BDI will never reset to 100%. A quick check is to have the battery on the charger, then quickly swap it onto the truck before the battery voltage drops down to normal.
The charger needs to push the battery to 2.44V/cell before it's actually 80% charged, 2.5V/cell @ 100%.

As for the code 80, if the pot tests ok on the display, then I'd start checking the over-mast harness. There are usually some spare wires, if you happen to find a bad wire.

Hope this helps...

hi, Mr Duodeluxe:
First, i had a question.
Every electric suitable for each model. If a model needs 210AH, you replace 210AH, useing 280AH, it would hurt the machine.

Secondly, maybe you can check the controller, there is something wrong.

Hope my suggestion would help you.
If you have any question, you can ask me.

Best Regards
Moon