[Al Skierkiewicz]

Canon,
The short to the frame is an issue due to wiring errors, bare wire or lack of insulation. The 2000 ohms to frame is a normal condition with CIM motors that have been used for a while. The carbon dust worn from the brushes collects on the end bell of the motor inside and causes some leakage currents. When they get below 2000 ohms I start to worry. I speak to the drive train because you seemed to indicate the issue occurs only when driving. On the meter you show, if you set it to the position just below ohms, it will beep when you have a low resistance connection. If you find anything that beeps when one probe is connected to the frame, you have a serious problem.