Solenoid not clicking,cart slowly shutters forward

[smokin3000gt]

Hello everyone. We've got a CCP with Alltrax controller and MZJ-400 amp solenoid. Have driven it a bunch since the upgrade without issue. Last drive was 4th of July, drove great, parked it and plugged it in. Went to go drive it the other day and the cart barely creeps/shutters forward. I noticed that I'm not getting the 'click' of the solenoid closing. I checked voltages, battery pack, and connections.

Can I jump the solenoid with 12v or does it need 48v 'engage'? Any other way to bench test it before replacing it? What would cause it to go bad after only a few months?

[Mooncarter]

Does that solenoid have a resistor across the 2 big posts? If so does it get hot when the cart tries to move?

[smokin3000gt]

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[smokin3000gt]

Originally Posted by Mooncarter

Does that solenoid have a resistor across the 2 big posts? If so does it get hot when the cart tries to move?

It does but I can't tell if it gets hot because I can't get to it when it's all back together. There is also a resistor or something like it between the two smaller connections

[Mooncarter]

The one on the small posts is a diode. I don't know anything about Alltrax controllers, but if it was mine this is what I would do: Jack the rear wheels off the ground. Tap the side of the solenoid with a rubber mallet, short piece of 2x2 wood or something similar while the pedal is slightly depressed. I think you may have a solenoid that is stuck open.

[NoleFan4Ever]

If you read the blink codes when you are depressing the pedal, you are more than likely getting a "Pre-Charge Failure" and you will also see that in the Alltrax Tool Kit. I do not know what is up with the MZJ's lately, but I have had 2 do that within as many months.

As MC stated, get a wooden hammer handle and tap very sternly on the side as the bridge is failing to properly close in and deliver current across the large posts.

I have this 2nd one on the bench and will be dissecting it for a Root Cause analysis as soon as things slow down.....

[smokin3000gt]

Thank you gentlemen, I will give that a try and follow up here after in case someone else runs into the same issue.

Is this solenoid going to be prone to doing this now? I hate to be away from the house with the family and have a failure or to have to take everything apart every couple months. Would I be better off in just replacing it?

[smokin3000gt]

Follow up questoin, can I manually engage the solenoid to see if it's fixed with 12v on the work bench or does it need to be 48v?

[NoleFan4Ever]

Originally Posted by smokin3000gt

Follow up questoin, can I manually engage the solenoid to see if it's fixed with 12v on the work bench or does it need to be 48v?

It needs 48v to properly activate the field coil.

[NoleFan4Ever]

Originally Posted by smokin3000gt

Thank you gentlemen, I will give that a try and follow up here after in case someone else runs into the same issue.

Is this solenoid going to be prone to doing this now? I hate to be away from the house with the family and have a failure or to have to take everything apart every couple months. Would I be better off in just replacing it?

I have them everywhere and on so many carts. These are the first 2 I had fail like this I attributed the one on my lithium to the higher voltage prematurely weakening the coil. But now the one quit on a regular Series cart so I believe it is more in the bridge then anything. A bump (actually 3 or 4) with it jacked up and pedal depressed and it would "click" and go....