jonnieZG:
The accelerometer requires very little power, so powering it from the Arduino should not be causing the issue per se. However, WT draws around 500 mA
I've just been going over my new standalone system's current requirements and your 500mA figure had me do some digging on that subject. For a long time I've had 38mA in my head but I'm no longer sure where I picked that figure up from but if our numbers are anything to go by, it definitely needed clearing up.
Turns out not one of the datasheet for the -16p modules holds any info regarding the devices electrical characteristics, or a schematic for that matter, which is a bit odd.
I eventually found what I was looking for in the -U datasheet (which does include schematics so not sure why the others don't).
I'm going out on a limb here but considering the -U is essentially the same module with a few extra pins, it's probably ok to assume that the characteristics we are interested in are shared across the range, and according to the info, the largest current draw is 200mA used for PWM speaker driving:
