95 medalist. cart shudders and jumps

[roughtruck]

M- to b+ full throttle I only have 15v. And on my speed controller white wire 1.5v full throttle

[roughtruck]

Also on another note how can I tell what my lift kit is. I was told it had a 6 inch axle lift but it sit about 2 inches lower than my dads 2012 txt witch I put the 6 inch spindle lift on myself. On mine if I measurefrom bottom of axle to bottom of the spindle its 4 inches. So makes me believe I have a 4 inch lift

[roughtruck]

Also black wire at thottle I have 15v when you push gas down. With back wire unhooked from throttle

[JohnnieB]

Originally Posted by roughtruck

Sorry been awhile since I have had time to work on cart. Since last time I have ohmed all cables and they are all good but replaced them anyway. Rechecked the f/r switch. When I ohm the motor (cables unhooked and motor out of cart) s1 to s2 I get 00.1 ohms a1 to a2 I get 00.1 ohms. Also both a1 to motor body 05.0 ohms and a2 to body 05.0 ohms

A1 or A2 to motor case should be 1,000,000 Ohms or more. Sounds like you've got a lot of carbon dust build up, or wires touching touching case.

[roughtruck]

Those readings were with motor out of cart sitting on my bench. It was laying on its side so wires were probably touch case. Im thinking its a problem with the speed controller im not getting full voltage out of it

[JohnnieB]

Originally Posted by roughtruck

Those readings were with motor out of cart sitting on my bench. It was laying on its side so wires were probably touch case. Im thinking its a problem with the speed controller im not getting full voltage out of it

The batteries, speed controller, F/R switch and Motor are connected in series. Attached is a simplified drawing high current circuit of a series drive.

If the battery has 38V the voltage across the B- and M- terminals on the controller should be 38V when the solenoid first clicks.

If it isn't, you have an open or excessive resistance in the high current circuit external to the controller.

If it is, the voltage between B- and M- should drop to nearly zero when the pedal is pushed to the floor.

If it doesn't, either the throttle input to the controller is bad, or the controller is bad.

However, if the voltage is roughly 1/2 of the battery pack voltage, the 1/2 speed reverse may be activated. (Voltage on Pin-3 activates 1/2 speed reverse.)