36v Troubleshooting and Diagnostics

[nickdalzell1]

The resistor only protects the controller from surge current and makes the cart take off without that 'bunny hop' off the line.

Have you checked the motor itself? It could be bad. If you have a multimeter set to continuity (beeps when leads touch) find S1 and S2 and A1 and A2 on the motor--it's usually stamped or labeled and sometimes the cables connected to it and/or the F/N/R are labeled as such. Find S1 and S2 and put your meter leads on that. then do the same on A1 and A2. if you get a beep with both tests the motor should be fine. If one test beeps and not the other part of the motor has gone open.

[mgm1986]

Yep, motor tested good with continuity and I was able to get it turning on 12v. I'm convinced it is the controller and as soon as I get the ebay seller to refund me I am going to contact ScottyB for an Alltrax.

[mgm1986]

Ended up purchasing the SR48400 from ScottyB with the 400 amp solenoid. Eventually I plan to upgrade to 48v and possibly larger tires so this should give me the flexibility to do so in the future.

Thanks to all who helped me troubleshoot!

[mgm1986]

Alright, new Alltrax SR48400 with 400 amp solenoid arrived today. Thanks, ScottyB!

After carefully installing the new controller and solenoid, the controller is not powering up (status LED isn't coming on).

Before I go any further, is there something simple I might be missing?

Pack voltage is at 38.6v.

[JohnnieB]

Make sure it is wired as shown on attached SR in Marathon schematic.

[mgm1986]

JohnnieB nailed it. I was plugging my BLUE wire into the blue plug (for reverse). This was clearly wrong but the colors matched! After connecting it to the proper terminal (KSI) she came to life!

Thanks to all who helped me get the old cart running. She runs great, forward AND reverse

Now I need to figure out the best throttle curve. I hit 100% throttle when the pedal is about 60-70% depressed. Bugs me but it works fine. Neighbors must get a kick out of me driving around the cart with a laptop on the passenger seat

[JohnnieB]

I'd start by checking the pot-box Ohms with pedal up (ought to be about zero Ohms) and make sure it advances smoothly to about 5,000Ω as pedal is slowly pushed to the floor.

Then clear the Auto-Cal. See attached image.

Once that is done, tweak the Throttle Linearization curve.

Then the Speed and Torque curves.

[mgm1986]

I will definitely give that a try. Thanks, JohnnieB!