36v to 48v Conversion – No Solenoid Activation

[Tj13]

Recently converted my 2002 TXT 36v to 48v. Based on the modifications completed previously, all that should have been required to finish the conversion is; batteries (6-8v), Delta Q charger port (and charger), 470 ohm resistor for the solenoid, and moving the SW202 negative from B- to the 4th battery negative post for 32v (the reversing contactors are rated for 36v). Once this was complete I got no movement from the cart – accessories (lights/horn/Aux/Battery gauge) did work though. I checked for voltage beginning with the Reed Switch - 50.3v, Key Switch – 50.3v, Accelerator pedal (MS3) – 50.3v, and then small + post on the solenoid – 50.3v. No solenoid activation or “click”. I bench tested the solenoid and did achieve activation to make sure it was not frozen. I also swapped out the solenoid with a new one for S&G’s, but same result.

I’ll also share the SW202 is not activating as well. not sure if this the result of, In addition to, or causing to the overall failure. I did attempt solenoid activation with the SW202 disconnected, but again same result as before.

I’m at a loss and it pains me to think I’m considering loading my cart up and haul to someone else to diagnosis the problem. It seems like it should be a simple fix that I’m just missing?

Additional info:
• Alltrax SR400 Controller
• MJZ400A Solenoid
• SW202-36v
• AMD 7122 EZ Spd motor
• 2ga. Cables throughout

[ThreeCW]

Originally Posted by Tj13

I checked for voltage beginning with the Reed Switch - 50.3v, Key Switch – 50.3v, Accelerator pedal (MS3) – 50.3v, and then small + post on the solenoid – 50.3v. No solenoid activation or “click”. I bench tested the solenoid and did achieve activation to make sure it was not frozen. I also swapped out the solenoid with a new one for S&G’s, but same result.

Welcome to BGW.

So your 48 volt MJZ400A Solenoid bench tested but does not operate in the cart.

When you checked 50.3 v to the "small positive post on the solenoid" did you test this to the battery pack negative or to the small negative post on the solenoid?

I assume that you changed your voltage settings of your Alltrax to 48 volts ... I wonder if you missed changing something in the controller in your upgrade from 36 volts to 48 volts?

If you did the former, it makes sense that you saw the same 50.3 volts no matter what was happening on the small negative post of the solenoid.

If you did the later (solenoid small positive post to solenoid small negative post) and saw 50.3 volts ... as you saw with your bench test, the solenoid should operate ... otherwise you have a faulty solenoid (that bench tests)

Perhaps post the Alltrax wiring diagram that you followed for wiring up your cart (with any modification you made marked on it) and perhaps those BGW members more familiar with the Alltrax controllers can assist you with trouble shooting.

[Tj13]

I tested to pack negative.

From what I've been informed, the SR Alltrax controller is capatable with 36/48v "out of the box".

I've attempted to upload the wire diagram, but i'm not able to make the file small enough to the fourm requirements.

I provided incorrect information in my original post when stating the voltage at solenoid small positive post:
• 50.3v with J1/KSI and SW202 positive leads removed
• 15.8v with J1/KSI and SW202 positive leads (32v negative) attached
• 7.8v with J1/KSI and SW202 positive (48v negative) attached

I have also put a call into Alltrax C.S. for additional support.

[Tj13]

BIG Shout Out to ALLTRAX Support! And Scotty B. too - very helpful and patient as well.

I forget the tech’s name that helped me, but the dude was super helpful and patient. He walked me through about 15 tests before we finally found the culprit. Turns out the reed switch was failing under load. I could get 50+volts to the solenoid, but it would drop to 7.8v when the pedal was pushed. So now the blue wire to the key is direct wired to the pack positive and works like a cham.

Thanks again for all your help and guidance!

Tim