EZGO GO Then No Go

[Shreadman]

2001 EZGO TXT Serie Cart
NPX4844 Controller
400 Super Solenoid (New)
48 Volt
Plum Quick Motor

Cart will sometimes run just fine then it will not run at all. With cart jacked up gas pedal pushed solenoid click, green light on controller, full throttle light changes to amber sometimes other times it stays green. Voltage at B+, B-. and M- is 47.6, pack voltage reads 50.1. at full throttle these voltages stay the same.

This started several months ago, I have replaced the ITS, micro switch, and solenoid (damaged old solenoid tightening nuts without removing (-) battery cable) lesson learned the hard way.

Does this sound like a controller or F/R switch issue

[JohnnieB]

Might be more than one problem.

1. Throttle issue. Follow gray cable out of pedal box to cart's wiring harness. and you should find a 4-pin in-line connector. Replace it with butt-splices or solder joints. That ought to take care of green LED not turning to amber every time pedal is pushed to floor.

2. Cart running issue. Does solenoid click when cart doesn't run?

If it does, measure between controller's B- and M- terminals with voltmeter.
When pedal is pushed just far enough to make solenoid click, you should read full battery pack voltage (50.1V?)

If you get it, press pedal slowly to floor and the voltage ought to smoothly decrease to 0V, or very close to it.




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I've gotta shut down for the night, but I'll be back tomorrow.

[Shreadman]

Thank You for the reply Johnny B

Might be more than one problem.

1. Throttle issue. Follow gray cable out of pedal box to cart's wiring harness. and you should find a 4-pin in-line connector. Replace it with butt-splices or solder joints. That ought to take care of green LED not turning to amber every time pedal is pushed to floor.

I have replaced all these wires and eliminated the connector. Read in another post that these connectors sometimes cause problems.
2. Cart running issue. Does solenoid click when cart doesn't run?

Yes the solenoid clicks every time pedal is pushed.

If it does, measure between controller's B- and M- terminals with voltmeter.
When pedal is pushed just far enough to make solenoid click, you should read full battery pack voltage (50.1V?)

If you get it, press pedal slowly to floor and the voltage ought to smoothly decrease to 0V, or very close to it.

I believe this is one of the test I did, and I got the 47.6V and the voltage stayed the same when pedal was pushed all the way to full throttle. I will re-check this, have rear end cover off waiting for paint to dry, and changing gear lube.

[JohnnieB]

Since the solenoid clicks while cart is misbehaving, the problems are in the high current circuit. Motor, controller, solenoid, F/R switch assembly, cables and throttle.

Not getting Full Battery Pack Voltage between B- and M- is a secondary problem that may limit performance, but won't keep cart from working. After fixing the primary problem, it will be a matter of finding and fixing the excessive resistance in the high current cables, connections and contacts.

If the Voltage between B- and M- doesn't decrease when pedal is pushed, either the controller or the throttle is bad. The throttle circuit is in three parts, power source, ITS sensor and throttle position decoder. The ITS sensor is in the pedal box and the other two parts are inside the controller.

The voltage between the black and white wires on the NPX controller ought to be 10V with pedal up and 6V with pedal on floor.

[Shreadman]

Thank You again JohnnyB for the assistance. Got rear end cover back on tonight not much time for anything else (long day at that thing called work). Will hopefully get time to do some more testing tomorrow night, and will post results. I have a new HD F/R Switch on the way from Scotty B, if that doesn't fix problem will look at a new controller.

[Shreadman]

So I finally got some time to do some testing on cart.
With cart as it was on Tuesday:

1st Test: M- / B- Push pedal solenoid click full pack voltage 50.1, slowly push pedal all the way down voltage goes to 0, motor and wheels turning as they should.

2nd Test (everything same): M- / B- push pedal solenoid clicks 47.8,m slowly push pedal all the way down voltage drops to 28.2, motor and wheels turning as they should.

Received new HD F/R switch from Scotty B, change this out.

1st Test: same thing as 1st test above.

2nd Test: M- /B- push pedal solenoid clicks get 48.1 volts, slowly push pedal all the way to floor voltage drops to 25.7.

Motor and wheels are still working as the should, they are turning.
Did the test several more times and sometimes get full pack voltage and drops to 0, and sometimes get lower than pack voltage and drops to around half.

Checked the white and black wire from ITS to controller with pedal up only getting .7 / .8 volts push pedal down get 5.8. Switched out ITS with old one get same readings.

I just had all my cables (ones to motor and controller along with all battery cables) off cart and cleaned and checked all for any cuts or rubs.

Not sure where to go from here, gonna take cart to campground this weekend and see how it does. During all the test I did tonight the EZGO was a GO, just some strange readings.

[Shreadman]

Another question I am hoping someone can answer. There is a small black wire that runs form the (-) side of the solenoid that goes to the back up buzzer, is this wire needed if I do not use the buzzer?

[Shreadman]

Update on GO NO GO

So I get cart to campground Friday, back off trailer cart runs fine, made some short runs with it Friday night no problems. Pull cart up on porch installed wind shield, and put water in batteries. Back cart off porch it hesitates and then kinda jerks on goes, put cart in forward ran about 50 feet and cart just stops, push pedal nothing solenoid clicks but NO GO. Lift seat up everything looks good try cart in forward and reverse again NO GO, wait a couple of minutes and then it goes. Drive it a short trip to another camp site, have dinner and head back to my place, cart goes in reverse then shift to forward drive about 50 yards and just stops. Check everything under seat, push cart forward push pedal NO GO, push cart backwards push pedal NO GO, pushed cart back to camper put her to bed, this morning it was a GO for a short trip, scratched my head and put her away, time to head home still scratching my head.

My thought at this point is with the controller. Any thoughts or suggestions would be greatly appreciated.

STILL SCRATCHING MY HEAD!!!

[DubK]

Originally Posted by Shreadman

Update on GO NO GO

So I get cart to campground Friday, back off trailer cart runs fine, made some short runs with it Friday night no problems. Pull cart up on porch installed wind shield, and put water in batteries. Back cart off porch it hesitates and then kinda jerks on goes, put cart in forward ran about 50 feet and cart just stops, push pedal nothing solenoid clicks but NO GO. Lift seat up everything looks good try cart in forward and reverse again NO GO, wait a couple of minutes and then it goes. Drive it a short trip to another camp site, have dinner and head back to my place, cart goes in reverse then shift to forward drive about 50 yards and just stops. Check everything under seat, push cart forward push pedal NO GO, push cart backwards push pedal NO GO, pushed cart back to camper put her to bed, this morning it was a GO for a short trip, scratched my head and put her away, time to head home still scratching my head.

My thought at this point is with the controller. Any thoughts or suggestions would be greatly appreciated.

STILL SCRATCHING MY HEAD!!!

Unfortunately I can't help you I'm new to this stuff. But I feel your pain. I'm having similar frustrations myself. I would guess you need a new controller. Just changed all my cables out, brand new 400amp solenoid, and brand new batteries and I can't get my cart to go at all. Scratching my head too. Very frustrating these electric carts are!

[JohnnieB]

It's time to replace the NPX with a SR48400 (or larger) anyway.