Help with intermittent rev no forward 2007 EZGO txt

[winger_wing]

Hey everyone,

First timer here, in advance thanks for any help much appreciated

Here’s the problem,


I have a 2007 EZGO txt pds

Will intermittently go in rev an have no forward, had a cpl buddies on it with me last weekend an it just died thought batteries were dead went an charged problem is still there. Took the cover off the controller box and there was a white sure that runs from my controller to the motor melted against the solenoid, replaced still have the issue. The resistor between the two large post on the solenoid (with key turned on) is getting burning hot, like to hot to touch.

Any help would be greatly appreciated

Thanks everyone

[bronsonj]

white wire that was melted?

Where does that wire go? Charge term or field coils on motor or?

[scottyb]

Controller is could be toast. Big white wire was F1 melted onto the solenoid...
Post a picture of what happened.

[winger_wing]

Thanks for the reply scotty and bronson

Here’s a pic and yes you are correct Scotty it is the white wire from F1 terminal on the controller

[winger_wing]

If it is the controller is there a way I can test before purchasing a new one and any recommendations on a good reman one?

[winger_wing]

Anyone have anymore suggestion would be greatly appreciated for the help

[yurtle]

Originally Posted by scottyb

Controller is could be toast. Big white wire was F1 melted onto the solenoid...
Post a picture of what happened.

The pic you posted was controller. I didn't see the melted wire?
Does it still go in reverse? Check stickies for PDS troubleshooting and manuals.

[winger_wing]

Yes it still does go in reverse occasionally, and the white wire I’m holding in that pic is the one that melted I replaced it. I will check the sticky’s for some troubleshooting

[JohnnieB]

Originally Posted by winger_wing

Yes it still does go in reverse occasionally, and the white wire I’m holding in that pic is the one that melted I replaced it. I will check the sticky’s for some troubleshooting

A sepex controller like the one used in a PDS cart is actually two controllers in the same box. A high power one that passes amps to the armature and a low power one that passes amps to the field windings.

The set of MOSFETs passing amps to the armature in a stock PDS controller will pass a maximum of about 300A, while ones passing amps to the field only passes about 1/10 of that amount and can pass them in either direction.

If the conductor of the white wire touched any of the solenoid's terminals, the field controller got hit with full battery pack voltage and the output is usually just a few volts, so the field controller was severely overvolted, or shorted out depending on the direction selected at the time.

To check the field controller:
Raise rear tires off ground.
Place F/R in F.
Connect DVM between F1 and F2 terminals
Press pedal to floor (3-4 seconds only)
The reading should be +2.7V +/- 0.5V.
Repeat with F/R in R and voltage should be -2.7V +/- 0.5V.