Did My Resistor Fry?

[Doc]

2000 Carryall Turf 1 48v. Wife was driving cart and it crapped out about 50' from our house. Went to tow it back and smelled a *slight* electrical smell. The diode that goes across the solenoid was hotter than hell! Cart won't move, but when you depress the pedal, you'll hear the click from the solenoid, but no movement. Replace diode? Oh, and which forum sponsor should I use? TIA!

[WalterM6]

That's not a diode, it's a resistor. When that happens it usually means your motor or controller or maybe both died.

[Doc]

Any way to test this?

[Fairtax4me]

So you need to determine if the motor failed. Typically the resistor cooking is because the controller has failed. Usually that's because of the motor posts being shorted together, which could be from a bad cable, or something metal bridging the motor posts, or something internal in the motor failing.

Inspect the cables to the motor for damage, and any sign of overheating/burning.
If the cables look OK, remove all of them from the motor. Be sure to use a wrench to hold the lower nut to prevent any of the posts from spinning.

With the Cables removed Check the motor for continuity.
A1 to A2 should have continuity.
F1 to F2 should have continuity.
You should have No Continuity from any A post to any F post.
You should have No Continuity from any A or F post to the motor case.
If any of those test fail, the motor needs to be repaired or replaced.

If the motor checks out OK, you can test it further with a 12v battery, but its usually not necessary if the continuity test is fine.
Make sure none of the cables are damaged, especially the smaller cables to the F1 and F2 posts. If those are compromised they will short out and damage the controller.

The controller you have is damaged, when one of the FETs in the controller is shorted it creates a high current draw across the resistor which is what causes it to heat up and let the magic smoke out.
That can usually be refurbished by any of several companies.
If you would rather buy a new controller, get an Alltrax. The Alltrax XCT controller has built in short circuit protection so it won't burn out if there is a motor failure or accidental short across the motor posts.

Any of the site sponsors in the Site Sponsors page. Generally Revolution Golf Cars, or ScottyB's Carts Unlimited are the go-to guys for motors and controllers. Both are super helpful and can get you exactly what you need.

[Doc]

Thanks for the replies...I'll get the meter out tomorrow and do some checking...meanwhile-worth mentioning-When I inspected the cart right when I got it back home, one of the lugs on the F/R switch was super-loose. Would that have been enough to fry something?

[Fairtax4me]

Oh, is this a series cart?
If so then disregard all of that from above.

[Doc]

It is a series cart....