Bad Solenoid?

[PearlPack]

2012 PH Precedent. Allied Lithium batteries, 2g wires, PQ bandit. Stock solenoid and stock controller.

I posted this question on the Allied thread on the Lithium board...but thought it might get more visibility here.

I installed new Allied Lithium 80ah (4 x 12v) batteries about a month ago and upgraded to 2g wires at the same time. Removed the OBC as I have the Allied charger. Everything has worked fine until now.

This weekend I took my cart to the beach. It worked fine for about an hour. Then it started jerking. It was not low on charge and no wires are loose. It started out happening infrequently but progressively got worse. In fact later in the day I thought I was going to get marooned but I limped the cart home by feathering the throttle for a couple miles.

Then it dawned on me that I can no longer hear any clicking from the solenoid. Could that be the issue?

It will still go but even as I was loading onto my trailer, it lunged like before.

I'm now home and tried to hear a click in my super quiet garage but nothing. (I could hear it before).

I don't know enough about solenoids to know for sure if this is my issue. Any help is appreciated.

[WalterM6]

Put your across the small terminals on the solenoid. You should measure 48v. If you DO and you can't hear it clunk the solenoid is bad.

[NoleFan4Ever]

And as Walt pointed out, if you do, tap on it with the butt of a wooden hammer and sometimes iif it is stuck that will free it up.

[PearlPack]

Put my voltmeter on the small terminals?

It's gonna be tough to get to it and keep everything connected....but I'll try. Thanks

[Fairtax4me]

On a precedent you need to lift the rear of the cart on jack stands to get to the solenoid from underneath. It can be done through the access opening in the bag well, but it's a long reach over the motor and through wiring. If you don't have a jack that will get it up high enough try driving the back wheels up on wheel ramps.

You can also test the solenoid with it removed from the cart.
With wires disconnected from the solenoid check resistance of the coil (small terminals). If it shows 0 ohms or infinite (O.L., or ~ or 1 on meter display) the solenoid coil has failed.
Check for continuity across the large posts. You should have No continuity.
Use jumper wires to apply 48v to the small terminals, be sure to note polarity if the solenoid has a diode built in. With positive and negative applied, you should hear and feel the solenoid click. Then test the large terminals for continuity again. You should have continuity. Remove power from the small terminals and the solenoid should click again and continuity should go away.

[PearlPack]

Update: Batteries are fully charged. The Solenoid click is there so I must have just missed it last night when the seat was still on. I didnt measure the small terminals since I could hear the click.

I just took it for a spin and the jerk is still there. Interestingly enough, when I drive at a snail's pace it doesn't jerk.

Could it be the stock controller?

[Fairtax4me]

Could be the MCOR going bad. With the cart off, pump the Go pedal full stroke 40 times or so and then drive and see if the problem is still there.

The other option is your batteries are not able to provide enough amp flow for the cart to operate properly. This will mean the cart can drive OK at little or low throttle, but will jerk with heavy throttle (accelerating under load) due to the lack of current flow from the pack.

[mrgolf]

hummm I,m thinking brushes in motor.

[PearlPack]

Just did the 40 pumps and the problem is still there. I guess it's time for a new MCOR?

I REALLY don't want to think about the batteries given I just dropped 3 grand on the Allied Lithiums. If it were the batteries, wouldn't the problem existed from day 1? I went a month with no issues after installing them.

[WalterM6]

I think it could be that the solenoid contacts are burnt/pitted. What you described when driving at a snail pace is what happens when the solenoid is bad and you're drawing current through the precharge resistor. Carefully feel if the precharge resistor is getting very hot. It's either that or you burned up your motor with your new fancy batteries.