2007 EZGO TXT PDS Motor Issues

[EZGoinPa]

I have a motor question concerning replacement or rebuild. Cart is a 2007 TXT PDS with motor (now removed) DE2-4007. Cart would not move, verified f/r switch, solenoid, resistor, all wiring and batteries with correct charge. Voltage was present at A1 (35.4 VDC) but at A2 it was 6.1 VDC. Service manual pointed to motor being bad. Motor was pulled and smelled 'burnt.' I need to check the resistance of the winding and armature and haven't yet. Has anyone experienced this? Does the motor need cleaned and brushes/bearing replaced or does it need replaced? Any help would be greatly appreciated.

[scottyb]

The burnt smell is distinctive. It cannot be user repaired, if it's not too far gone it can be refurbished by PQ motors or EMP

[JohnnieB]

Originally Posted by EZGoinPa

I have a motor question concerning replacement or rebuild. Cart is a 2007 TXT PDS with motor (now removed) DE2-4007. Cart would not move, verified f/r switch, solenoid, resistor, all wiring and batteries with correct charge. Voltage was present at A1 (35.4 VDC) but at A2 it was 6.1 VDC. Service manual pointed to motor being bad. Motor was pulled and smelled 'burnt.' I need to check the resistance of the winding and armature and haven't yet. Has anyone experienced this? Does the motor need cleaned and brushes/bearing replaced or does it need replaced? Any help would be greatly appreciated.

Something is amiss with those readings.

B+ from the solenoid connects to A2, so it ought to read full battery pack voltage whether the motor is good or bad.

Also, 35.4V is only about 30% SoC (State of Charge). Full charge is about 38.2V.

Here is how to test a sepex motor. It doesn't have a front bearing, so it has to be mounted on differential to test.

[yurtle]

I assume since he's moving cables around, he could use the solenoid as the battery cut-off switch? Don't simply hold two cable ends together or hold it to the motor, as the two may weld together and/or damage the lugs. Not to mention molten metal flying in you hands or eyes.

I still have my original cables, and could sacrifice them for a quick and dirty "switch", using gloves and eye protecction.

[EZGoinPa]

Sorry about the terminal readings, I had them reversed. A2 had the full voltage and A1 was at about 6 volts. As far as the SoC, these batteries are older and we charged them about two weeks ago and with trying to find out what was going on, we ran them down. I have not charged them yet, and we used a load meter to check each of them. I know they are a little weak at the moment, but it shouldn't be enough to not allow the motor to run.

[JohnnieB]

Having pack voltage on A2 and ~6V on A1 only means there is a 6V voltage drop across the MOSFETs in the controller and two high current cables, which in turn could mean the peddle was not pushed all the way to the floor or the resultant throttle signal wasn't telling the controller to go to 100% duty cycle.

What voltage do you get between F1 and F2 with pedal on floor?

What Ohmic readings do you get between A1 & A2 and between F1 & F2?

[EZGoinPa]

I will check the resistance on the motor and get back to you tomorrow with that. Unfortunately my buggy is at our campground and I won't be able to further troubleshoot until this weekend. I greatly appreciate all the ideas and assistance. As soon as I measure the voltage and if I discover anything else, I will let you know.

[JohnnieB]

[EZGoinPa]

Ok, so the resistance readings of the motor are as follows:
A1 - A2: Open
A1 - GND & A2 - GND: Open (not shorted to case)
F1 - F2: 1.4 Ohms
F1 - Gnd & F2 - Gnd: both open (not shorted)

I do believe I should have resistance between A1 and A2. I even set my meter on highest resistance setting to verify that it is open, and it is.

[BobBoyce]

Originally Posted by EZGoinPa

Ok, so the resistance readings of the motor are as follows:
A1 - A2: Open
A1 - GND & A2 - GND: Open (not shorted to case)
F1 - F2: 1.4 Ohms
F1 - Gnd & F2 - Gnd: both open (not shorted)

I do believe I should have resistance between A1 and A2. I even set my meter on highest resistance setting to verify that it is open, and it is.

Yes, you should read under 1 ohm across the A1 to A2. Since it is open, I would check the brushes and brush holders first. Sometimes as the brushes wear, the stranded leads attached to them hang up and prevent the brushes from making solid contact with the commutator bars. Or they could just be worn out. It's also possible that brush leads could have broken loose from the A1 or A2 lugs. They are usually welded to the heads of the lug bolts.

Bob