Best golf cart speed controllers: Alltrax and Navitas by cart

A golf cart speed controller is the part that decides how much current the motor gets, and the stock one is set to 250 or 300 amps. Replacing it with a 400-amp programmable controller is the one performance upgrade that pays off on a stock motor: better hill speed, 2 to 4 mph on the flat, and a top speed you set yourself instead of a dealer. Buy it by motor type first, because a series controller on a sepex motor does nothing useful. Then pick amps, and buy the solenoid and cables that go with them.

For most carts the answer is an Alltrax 400 or a Navitas 440 at about $450 to $800. Past that, the controller comes with a motor.

Series, sepex or AC: this decides everything

Series motors have the field and armature in one circuit; the controller only has to manage one pair of wires. Club Car DS from 1995 to about 2000, EZGO TXT series carts (the ones with a forward and reverse lever) and the 36V Yamaha G14 and G16 are series. Controllers: Alltrax SR, Navitas series.

Sepex, or shunt, motors have a separately excited field the controller drives, which is how it manages regen braking and the speed code. Club Car IQ (DS from 2001, Precedent 2004 to mid-2008) and Excel (Precedent from mid-2008, Onward and Tempo), EZGO PDS (2000 to 2009), DCS (1996 to 1999) and the TXT48 from 2010, and the Yamaha G19, G22, Drive (G29) and DC Drive2 with their Hitachi shunt motors are sepex. Controllers: Alltrax XCT, Navitas sepex (Navitas calls them shunt).

AC carts have a three-phase motor and an inverter. EZGO RXV and Yamaha Drive2 PowerTech AC are AC. The upgrade is a Navitas AC kit that replaces motor and inverter together.

The fitment finder sorts your cart by year, and the Club Car, EZGO and Yamaha fitment pages list the drive type by model year. If you are not sure, look at the motor: both types have four terminals, but on a sepex motor the F1 and F2 field terminals are lighter than A1 and A2, while a series motor’s four are all the same heavy gauge. The controller model number on the stock unit settles it.

Amps: 300, 400, 500 or 600

300 amps is a stock replacement. If your controller died, a 300-amp unit gets the cart back to how it was and no more.

400 amps is the upgrade. A stock motor handles it for the length of a normal hill, hill speed improves a lot, and you gain 2 to 4 mph on the flat. This is where most owners should stop.

500 and 600 amps are for a motor wound to take them. A stock motor at 600 amps overheats on a long climb and the insulation goes. Buy these as a matched motor and controller kit; the faster-cart guide covers when the kit is worth it.

Matching the motor and the pack

Match the type, then the current. A 400-amp controller on a stock motor is fine. A 600-amp controller wants its own motor.

Then match the pack. On flooded lead-acid, a 400-amp controller is fine with a healthy set and 4-gauge cables. On lithium, the BMS continuous rating has to be above the controller’s peak or the BMS trips on hills: 400 amps wants a 250-amp or better BMS, 600 amps wants 300 or more. The 48V lithium page lists BMS ratings for each pack.

Solenoid and cables

The stock solenoid is rated for the stock controller and its contacts burn under 400 amps. Fit a heavy-duty 400-amp solenoid, about $40 to $80, at the same time. Most controller kits include one or list the right one.

Cables carry the current and the stock ones are often 6 gauge. For 400 amps use 4 gauge; for 500 and 600, 2 gauge. Replace anything with green corrosion at the ends. The battery cable guide has lengths by cart and how to crimp them.

Programming from a phone or laptop

Navitas controllers use a Bluetooth dongle and a phone app. You set top speed, acceleration rate, regen strength and throttle curve, and the app shows live pack voltage, current and motor temperature while you drive. It is the easiest way to tune a cart and to see when you are working the motor too hard.

Alltrax controllers program from a laptop over USB with the Toolkit software, and some newer models add Bluetooth; check the listing. Either way, start with the maker’s default profile, set the top speed where you want it, then soften the throttle ramp if the cart chirps the tires from a stop. Set regen braking to taste; stronger regen saves brake shoes and feels like engine braking in a car.

Which controller for your cart

Cart	Drive	Pick	Notes
Club Car DS 1995 to 2000	48V series	Alltrax SR 48400	Club Car series version
Club Car DS 2001 to 2013, Precedent 2004 to mid-2008	IQ sepex	Alltrax XCT 48400 or Navitas sepex	Replaces the speed code
Club Car Precedent mid-2008 and later, Onward, Tempo	Excel sepex	Navitas 440 or 600 kit	Check the Excel harness is in the kit
EZGO TXT PDS 2000 to 2009	36V sepex	Alltrax XCT or Navitas sepex	Check the listing covers 36V
EZGO TXT series	Series	Alltrax SR 48400 or Navitas series	Lever forward and reverse
EZGO TXT48 2010 on	48V sepex	Alltrax XCT or Navitas TSX for the TXT48	Toggle forward and reverse; its own kit
EZGO RXV 2008 on	48V AC	Navitas AC kit	Includes the motor; see the RXV page
Yamaha G19, G22, Drive (G29)	48V sepex	Alltrax XCT for Yamaha or Navitas 440 or 600	Kits differ by stock controller plug (GE or Moric)
Yamaha Drive2 DC	48V sepex	Navitas TSX or 600 kit	Confirm DC on the plate
Yamaha Drive2 PowerTech AC	48V AC	Navitas AC kit	Includes the motor

The EZGO RXV upgrades page goes deeper on the AC conversion for that cart.

Install: about two hours

Disconnect the charger, lift the seat, and pull the main negative at the pack first. Photograph the stock controller wiring before you unplug anything. Remove the old controller, mount the new one on the same plate or the supplied bracket, and connect the heavy cables in the order the kit shows: battery positive and negative, motor A and F terminals, solenoid. Plug in the harness, fit the new solenoid, torque the terminals, and reconnect the pack negative last. Put the cart in tow mode, power up, and run the app or software to confirm it sees the controller before you drive. First test drive at a low top speed setting, then raise it.

When to stop and call a shop

If the stock controller is fine and the cart is slow, start with the speed code or tires, not here. If the motor smells hot after a hill with the stock controller, the motor is the problem and a bigger controller will finish it. And if you are putting a 600-amp kit on a cart with original cables, a tired solenoid and a 200-amp BMS, the controller will spend its life tripping things; the shop fixes the supporting parts first, and so should you.