Blown controller? neg-phase and pos-phase show similar R

[AustinP]

Hi there, I acquired a controller a few months ago and just got around to testing it recently. Upon hooking everything up (CA, battery, ignition, etc.), the CA lit up and seemed to be working fine. When twisting the throttle, nothing happened, although I did verify the throttle is outputting a variable signal (don't recall exact voltages, but it was linear with twist). I did open the controller before installation to solder on the 3 speed switch wires and it smelled like there was some of that magic black smoke at some point.

I just got done testing the FETs and there was continuity between all the phases with both pos and neg of battery:
neg-phases: all around 9.95k ohm
pos-phases: all around 15 k ohm but this value would climb the longer I held the test probes in place

Any ideas? The Grin MOSFET testing document shows only open and 100% short circuited scenarios... what does 50% higher resistance from pos-phases over neg-phases mean?

Thanks for any assistance.

 

[Drunkskunk]

Likely it's OK. If the capacitors still have a charge you will see a climbing resistance. It will be best to leave the controller unpowered for a while then retest the 3 phases to positive, but the important part is that none show a hard short.

 

[dnmun]

use the diode tester on your voltmeter. do not use the ohmeter. check for the body diode in the mosfet so measure both ways, on hiside and loside mosfets.