Is it possible to temporarily provide power to the MNGP2 with a 9V or 12V battery so that the firmware may be updated in the office?
not sure how far your office is from your power room , but I run a cat 5 cable from my hawkes bay about 20 or 25 feet to where I have mngp2 remoted and have always upgraded firmware at that point.
But you have an interesting question , if you provide the 9v to mngp will it turn on and then update ? I will be interested to know too if it needs the other Canbus comms connected back to device . My guess will be yes .
Larry
PINS 7&8 and it does not need CAN COMMS to power up.
9 to 12VDC is okay
After confirming that pin 7 (white/brown wire) is positive an pin 8 is negative (brown wire), I powered up a MNGP2 with a 9V battery and completed a firmware upgrade. In the future I'll make sure the MNGP2 firmware is upgraded before installation.