'06 36V series TXT wires getting hot.

[meimk]

As title says it's a 2006 36 volt series TXT. Motor appears stock, controller appears stock (Curtis 1206), but it has a lift and 22" tires. Owner I'm trying to help uses it to drive (slowly) around his acreage with moderate hills, tall grass and so on. He's used it this way for years, without a problem till now. We've already replaced the forward reverse switch with a heavy duty after the old one got hot enough to deform the plastic some & break contact. Now the cables to the switch (all 4) are getting hotter than I would like. With my infrared temp gun I'm seeing about 125(f) at the terminals on the switch but 150 or slightly more on the cables themselves. After driving 20 minutes or so it loses power. It seems to attempt to move but not have quite enough power. Give it a "push and it will slowly roll on. Battery voltage at that point was around 37.4, so isn't a lack of battery power. Could worn brushes be the culprit? Thoughts?

[JohnnieB]

Connect a DVM between the controller's M- and B+ terminals.
Push pedal to the floor slowly and the voltage should increase smoothly from 0V up to whatever the battery pack voltage is at the time.

If it does, brushes may be the problem.
If it doesn't, check the ITS voltage.

[meimk]

M- to B+ starts about 1.4 volts at solenoid engagement to 35.4 volts at full throttle (momentary). The 35.v is what I get across pack + & - when at momentary full throttle. ITS ranges from .545 to 1.67. Looking more and more like brushes.

[JohnnieB]

The motor is being told to run, but isn't doing it.

Hopefully $omething $imple like brushes.