Tricky Elec. Issue - Need to pick your brains

[konakid]

6-10 yr old 36 volt txt.

Rarely it - is dead when I step on the "gas" pedal. Rarely - it barely tries to move, but won't. And rarely - it will start moving, but acts like it is running out of juice (slows a lot on incline).

But only rarely. And if I wait, turn key on or off, flip F&R switch (dash mounted), it may start running great again - until next episode - could be in a week.

I have checked the battery pack voltages and connections. And while it seems like it could be a connection somewhere - sometimes it just starts working great after turning the key off and on - but only sometimes.

I have started listening for the various clicks I think I should be hearing. But I am not sure what is "normal." At times I hear what I think is the solenoid click when I turn the key, and at other times I do not. Same with the F&R.

What I'm thinking --- could this be happening........
When I turn the key off, sometimes I do not hear a click - should I??? Can a solenoid stick in an on position??? Would this make for intermittent or erratic episodes like this? Because sometimes when I turn the key on there is not a click, but it works fine (could the solenoid already have been stuck "on"?). And sometimes, there is no click and it doesn't move.

I guess I don't understand the various clicks. It seems there is one for the solenoid, one for the F&R, and one for the little switch on the "gas" pedal.

Am I making any sense? I guess I'm looking for some suggestions as to what to listen for (or test)- exactly. Problem is that it only happens infrequently. And the next time I turn the key, it could be fine again.

[stang99x]

Sounds like you have some old corroded wire that is probably run back into the insulation that you can't see. It would work sometimes, and other times the resistance would be to great to allow current to pass. That and check to see if any of the wires going to the motor have rubbed on the frame and created a bare spot that rubs metal

[konakid]

Thanks for the reply.

To be clear - are you speaking of possible corrosion on any of the wiring, or just the "fat" wires associated with the battery pack (and motor)?

I had a problem with that switch on the pedal before - but this caused it to either run or not run. I am assuming that now, since it sometimes tries to run, or will run like it is running out of juice, is why you are not suggesting a switch/solenoid/etc issue - and more of a full current from the battery pack issue.

Is my thinking accurate on that???

[stang99x]

The microswitch in the pedal assembly is pretty solid. If you've replaced it before chances are it is fine. I have had them go bad but not all to often. The corrosion I am talking about could be in any of the battery wires, motor wires and from time to time the smaller gauge wires get "burnt." Most of the time the burnt wires will be located at or very near to the solenoid.

To be clear, is it dropping off and giving you a master fail alarm or just dropping off and not running? Do you have a voltage reducer for accessories?

Just this week I had an old Ezgo PDS kicking my backside that would move a few feet and then the master fail alarm would go off and it would stop. After endless wire probing and testing I ended up finding that someone had "fractured" the post on the solenoid by not using two wrenches to tighten the nut. You couldn't tell until you took the solenoid off and wiggled the fractured arm. Sometimes the issues aren't visible. And those issues will just plain piss you off. But I've had carts do similar things with corroded wiring.....and the corrosion was inside the insulation and not visible.

[konakid]

The symptoms are very odd in that they are infrequent, but can be totally dead, a super weak attempt at moving (but not able to), or slowly moving and completely stopping uphill.

But, if I flip things around, and off and on, or wait, the next time I turn the key it moves along like it has newly charged batteries.

The microswitch is still old. What it was doing before was that it would not click "on" when then pedal was released - as I understand it, when the pedal is all the way up and the key is off, this switch is open, but is in an on position - ready for the key and F&R.

So, with this switch not closed all the way when in park and "off" - nothing happened when the key was on and the pedal was pushed. I had to realign and reposition it. It was only a hair's width of not operating as it should.

But that doesn't explain the "in-between" action. And I can't get a good read because it happens so infrequently. And when it happens, by the time I have turned the key on and off a few times and removed the seat to jiggle any wires, it is working again.

These intermittent issues can be so frustrating to pin down - especially when you know as little as I do.

[stang99x]

Yes, they can be quite infuriating. Just think, you only have to deal with yours. I have to deal with everyone's.....and nobody ever tells you everything when they break it. You really need to be able to test voltage during a failure....so you can figure out what isn't functioning properly. I would guess there is something causing a large amount of resistance that is at the point of failure.....still working but soon to die. Perhaps put on a new set of larger gauge wires as a start.

[stang99x]

Ugh I'm a tard. Is your cart a series? Like with a F/R handle on the body?

[konakid]

Well if you're a tard, then what does that make me? What's worse than a tard? :)

My problem is that I have sold this cart to someone who is helping me take delivery of a brand new electric utility "golf cart" in a couple of weeks. He will be trailering the new one to me (2 1/2 hrs - each way), when picking up this one, as part of a deal we worked.

So any time and money that goes into this one is up in flames for me - especially if it doesn't fix anything. And no deal, no free delivery. And he is a friend, so I don't want to sell him something I know has a problem.

But to answer your question, no - this has the F&R on the dash. Does that change anything you have said?

[stang99x]

Well no it doesn't change anything. I was thinking it sounded like a F/R cam that was burnt in a series style cart. But that's not relevant to a pds type. I really think you have some corrosion somewhere that it creating resistance intermittently and thus the root of your problem.

[konakid]

Please - one more follow up.

If I placed a "permanent" (remote) voltage meter on the two "main" poles of the battery pack, then used the cart as I normally do - if it is what you suspect - should I see the reading "freaking out"?

Would that be a good way to proceed if we suspect a cable corrosion issue?