48 volt 1999 Ezgo freedom electric that has stopped moving

[skyriver]

I have a upgraded 48 volt 1999 Ezgo freedom electric that has stopped moving. It has been erratic in its movement for a while now, the motor jerking and powering back acting like it wanted to stall as it moved along. I replaced the throttle sensor believing that was the problem, but it ran good for a half a day and stopped altogether.

The solenoid clicks like normal when I push on the accelerator, but hesitates about 5 to 7 seconds when I letup on the pedal. It use to click instantly when I both pushed and released the throttle pedal.

I'm using a altrax controller and the light is solid green when keyed on and when I push the accelerator pedal down it turns solid yellow.

Any ideas on what the problem might be?


Thanks
Den

[JohnnieB]

Series drive or DCS?

[skyriver]

It's a DCS.

Thanks Johnnie

[JohnnieB]

Alltrax DCX or Alltrax XCT controller?

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Might be brushes. Still running a stock DCS motor?

Check the F1/F2 cables for worn insulation were they are routed around the frame. (See attached picture)

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What is the cart doing now, running poorly or not running?

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Also, what is make/model and age of batteries?

[skyriver]

it's a Alltrax XCT, with a upgraded 17 hp motor a couple years old. I've got the cables between the controller and motor covered with protective wrap, but I'll check them tomorrow to see if there is a problem.

At present it is dead in the water outside of powering up and the solenoid clicks like normal when I push on the accelerator, but hesitates about 5 to 7 seconds when I letup on the pedal.

It use to click instantly when I released the throttle pedal. That' the only symptom I see outside of not moving. My first thought was that the motor failed, hoping it's not that. Batteries are 8 - 2 year old Crown 260's, still holding well.

Thanks Johnnie for all your help. I'll check the cables tomorrow evening.

[JohnnieB]

Is the XCT's LED flashing any error codes, or are any errors showing up on Toolkit's monitor screen?

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Measure the battery pack voltage.
Connect your voltmeter between the XCT's B- and M- terminals.
Press pedal just far enough to make solenoid click and you ought to read full battery pack voltage.
If you do, press pedal to floor and the voltage ought to decrease to zero.

[skyriver]

Ok I've gone through the cables and all is well, the protective cover is clean. I checked the XCT B- and M- connections and they are showing 50 to zero when I engage the throttle pedal and push it to the floor.

I believe the XCT is good, when I power up the XCT flashes green 4 times then stays green.

Thanks
Johnnie for all your help.

[JohnnieB]

If the voltage between B- and M- goes from 50V down to 0V, then the voltage between M- and B+ is going from 0V to 50V and the motor's armature is connected between M- and B+, so there is most likely a motor issue.

To run, the motor needs voltage between A1 & A2 and between F1 & F2.

Access the motor and verify you are getting the 0V to 50V between A1 &A2.
Check the voltage between F1 &F2. Voltage there is determined by the field map, which is motor specific, but will probable be someplace between 5V and 40V.

Also, you can try to run the motor on battery power. See second attachment.

Hopefully the motor just needs brushes, but also good time to replace bearings.

[skyriver]

OK I have 50 volts at the motor with the throttle pedal down. I also ran the motor test with a jumper between A1 and F1 and A2 and F2 and the motors spins so I guess it's motor, am I correct?

Thanks Johnnie

[JohnnieB]

Originally Posted by skyriver

OK I have 50 volts at the motor with the throttle pedal down. I also ran the motor test with a jumper between A1 and F1 and A2 and F2 and the motors spins so I guess it's motor, am I correct?

Thanks Johnnie

It is a sepex (separately excited) motor, so the armature windings and the field windings are excited (voltage applied to them) from separate sources. If you are getting 50V between the motor's A1 & A2 terminals with the pedal down, you also need to get someplace between 5V and 50V between the motor's F1 & F2 terminals to get the motor to spin.

The motor ran when you jumpered A1 to F1 and A2 to F2, so we know it runs.

That narrows it down the the low power portion of the controller that feeds the field windings, or the connections between the low power portion of the controller and the field windings in the motor.