Bad Solenoid? Confirm my diagnosis

[cheapjeep2]

Originally Posted by Sergio

Remove the pre-charge resistor and see if the cart still drives.

This is an Alltrax XCT-48500-IQ there is no pre-charge resistor. Just the two diodes, one on the main power lugs and one on the activations circuit.

I've installed these controllers before and this is unusual behaviour. If i get the same issues after trying the stock solenoid I am going to suspect something may be up with the controller.

[Sergio]

Your signature says DCX500, that is why I suggested the pre-charge resistor.

I did not notice the controller model you posted on the first post.

If the Regen diode is oriented properly the only other source of power if the Solenoid does not close is Pin #9 (Gray wire) on the Controller.

[cheapjeep2]

Originally Posted by Sergio

Your signature says DCX500, that is why I suggested the pre-charge resistor.

I did not notice the controller model you posted on the first post.

If the Regen diode is oriented properly the only other source of power if the Solenoid does not close is Pin #9 (Gray wire) on the Controller.

Interesting, this cart does not does not have an OBC, so I have leads that would go into the OBC joined and that is the red and gray wire. But still, this seems super odd to me as it's never done this before and I've had 3 IQ carts in this same configuration. Again, this makes me thing it's the controller. But will see.

[Sergio]

The gray wire from the receptacle that goes to the OBC should not be joined with a positive wire since a few chargers bring the gray sense wire to negative when you plug them into the cart.

Only the Blue and White wires should be joined at the OBC 6-pin connector to by-pass the lockout mode.

With the Alltrax XCT You can actually just leave the OBC 6-pin connector unplugged without any wire jumpers and change the setting in the software for the lockout mode.

The Gray wire I was referring to comes from the Tow/Run circuit and provides power to the controller when the key switch is OFF and you need the roll-away brake.

[cheapjeep2]

Originally Posted by Sergio

The gray wire from the receptacle that goes to the OBC should not be joined with a positive wire since a few chargers bring the gray sense wire to negative when you plug them into the cart.

Only the Blue and White wires should be joined at the OBC 6-pin connector to by-pass the lockout mode.

With the Alltrax XCT You can actually just leave the OBC 6-pin connector unplugged without any wire jumpers and change the setting in the software for the lockout mode.

The Gray wire I was referring to comes from the Tow/Run circuit and provides power to the controller when the key switch is OFF and you need the roll-away brake.

CORRECTION - I said gray... I actually meant the light blue and red, this is the what bypasses the lock out on this cart. The cart has no OBC at all and the gray wire to the charging port is disconnected. It has a DPI charger.


These are the right wires to fuse together for an OBC by-pass on this model. I've done it several times with out issue.

[cheapjeep2]

It is solved. It is indeed a bad solenoid. I removed the heavy duty 400 amp one and put in the stock solenoid, changed nothing and else and boom back to life.

That was a strange one.

[Sergio]

The Red and Blue wires together is one way to by-pass the lockout signal but I don't like that approach as it leaves +48v at the Controller 16-pin connector even when the Tow/Run switch is on Tow.

I think the White and Blue wires together is a better option since the White wire power comes from the Tow/Run switch so there is no power at the Controller 16-pin connector when the cart is on Tow.

As I mentioned before if someone has an Altrax XCT they don't need any wires jumped.

If You have a chance check the resistance between the small posts of the MZJ-400 to see if the bottom contacts are just stuck.

[cheapjeep2]

Originally Posted by Sergio

The Red and Blue wires together is one way to by-pass the lockout signal but I don't like that approach as it leaves +48v at the Controller 16-pin connector even when the Tow/Run switch is on Tow.

I think the White and Blue wires together is a better option since the White wire power comes from the Tow/Run switch so there is no power at the Controller 16-pin connector when the cart is on Tow.

As I mentioned before if someone has an Altrax XCT they don't need any wires jumped.

If You have a chance check the resistance between the small posts of the MZJ-400 to see if the bottom contacts are just stuck.

1st - Solenoid, i measure and I get zero ohms / open across the small terminals. Pulled bottom off and there is a small gap. if i press and hold the bottom shut it reads 16 ohms. This is with the solenoid not installed... bench testing. What is normal state, should the contacts be normally opened or normally closed on the bottom?


2nd - You say with an XCT nothing on OBC circuit needs jumped, what needs changed in the XCT then to make this work, I pulled the jumper off of the red and light blue wire and it does not work. i did jump the white wire to the blue as you mentioned and it works.

PS Thank you

[Sergio]

To change the Charger Interlock option on the XCT:

Open the Alltrax Toolkit software and click on Tools then Options.

Make sure you have a check-mark on the "Show Charge Interlock".

Go to the "Controller Settings" Tab and scroll all the way to the bottom of that page.

Change the option: "Disable the Motor Controller when User3 is:".

The options are: "Floating/NC" or "High/Low".

Change the current option to the other option.

Click the "Set" button (on the left of the Program) to save the settings

Your old Solenoid should be working now if it reads 16Ω.

Keep in mind that "continuity" test in most meters is below 250Ω so a 300Ω coil resistance would show no-continuity, some meters over-range also show 0L depending on the range.

With the bottom contact stuck if the L2 coil was really burnt, test the fly-back diode to make sure it is not open.

In the MZJ-400 dual coil design, the fly-back diode is critical to keep the L2 coil contacts from arcing.

[cheapjeep2]

Originally Posted by Sergio

To change the Charger Interlock option on the XCT:

Open the Alltrax Toolkit software and click on Tools then Options.

Make sure you have a check-mark on the "Show Charge Interlock".

Go to the "Controller Settings" Tab and scroll all the way to the bottom of that page.

Change the option: "Disable the Motor Controller when User3 is:".

The options are: "Floating/NC" or "High/Low".

Change the current option to the other option.

Click the "Set" button (on the left of the Program) to save the settings

Your old Solenoid should working now if it reads 16Ω.

Keep in mind that "continuity" test in most meters is below 250Ω so a 300Ω coil resistance would show no-continuity, some meters over-range also show 0L depending on the range.

With the bottom contact stuck if the L2 coil was really burnt, test the fly-back diode to make sure it is not open.

In the MZJ-400 dual coil design, the fly-back diode is critical to keep the L2 coil contacts from arcing.

Awesome - changed to the high/low and it works.... Very cool.

At this point I am not taking a chance on this solenoid again, as this car is for my in-laws that are in their 70s. I ordered a new MZJ.

I've also have a diode testor on my meter and the activation diode checks out. With Positive lead on the black side and negative lead on the silver band side in diode mode I get a reading of 630, when reversed there is no connection as it should be.