what parameter were you adjusting
im assuming you adjuster #15
thats for battery volts
setting function #15 anywhere between 32 and 44 tells the control its in a 36 volt truck
but thats not the BDI adjustment

you need function #14 "internal resistance compensation"
this alows you to fine tune the accuracy of the BDI

you have to do this test under load and do a lil math
you need a separate voltmeter that at battery voltage can read 100ths of a volt (ex: 36.57v) and a high current clamp on DC ammeter that can read 400 amps or more (DC)
you may need an assistant to operate while you take readings or vice versa (its tough to do alone)
so
jack and securely block the machine so the drive wheels are off the floor and can spin freely

clamp the ammeter to one of the motor cables in the control panel (where you can read it) i believe its supposed to go on the 1A cable
attach the voltmeter (+) to SCR positive (battery side of the 1 REC)
attach the voltmeter (-) to SCR negative (stud on lower left side of panel next to the current sensor)

remove or jump the brake pedal switch wires so that the wheels will move with the brake pedal applied

run the truck in fwd until 1A kicks in
the truck must be in 1A (high speed bypass) for this to be accurate
then start to apply brake while watching the ammeter
try to hold it at 100 amps, take the voltage reading and write it down
then repeat this but at 200 amps

V0 = 100 amp voltage reading
V1 = 200 amp voltage reading
Vd = voltage differential
Vd = V0 - V1

refer to the chart here for the setting based on the voltage differential
http img110.imageshack DOT us/img110/7905/resistancechartod4.png

for a mitsu 2fbc20 mitsu says to disconnect the power steering contactor coil
and that the dash display has to read anywhere in between 80 and 20