Club Car Golf Cart MCOR (Troubleshooting Guide)

Club Car MCOR troubleshooting

What is an MCOR in a club car?

The throttle device of any club cart is known as MCOR or motor controller output regulator. As the foot pedal is pressed, the impulse is read by the electric motor and works accordingly. Four types of MCOR are fitted with different models of club cart manufactured in different years.


This type of throttle device was used on all Carryall and DS models cars from the year 2000 and continued till 2012. It has a star splined input shaft, and the mounting is a bit different than other models. However, this type of model has become obsolete and is not readily available anymore.



The MCOR2 throttle device is used in club car Precedent. Apart from the mounting and the input shaft as such, there is no significant difference with MCOR1. They are still available in the market as of date, however, sometimes the pedal group needs to be changed, or a conversion kit is used to fir them to the cart.



Both these models are similar and fitted to Precedent and DS car models. However, MCOR4 functions poorly in comparison to its earlier version and is not that much popular.

The primary function of the MCOR is to sense how hard the pedal is being pressed and how much the controller needs to control the spin of the motor.


Club Car golf cart bad MCOR symptoms

The club cart bad MCOR symptoms are commonly diagnosed as a erratic throttle jump. While pressing the pedal, if the club cart’s throttle moves smoothly from 0% to 100%, then the MCOR is ok. 

  • However, if there are erratic movements, say like 20%, then 60%, and then 15%, and likewise despite keeping the pedal pressed with uniform pressure, the MCOR is giving trouble. It will never reach 100%. 
  • If it takes too much time for the MCOR reading to move up, the MCOR is malfunctioning. 
  • The cart will not get enough speed as the motor will not move as per requirement and movement hiccups of the cart indicate that the motor is not getting enough or erratic power signals. It is a sign of a bad motor controller output regulator or the MCOR.


Club car MCOR problems

  • If the operation of the cart is hesitant or jerky, it is a sign of MCOR problems. 
  • The club car MCOR or the motor controller output regulator works like a dimmer in the headlight. It determines how much power is needed to get the desired speed by modulating the voltage. 
  • The variation in the electric output is done by the MCOR to get the desired speed. However, if the desired speed is not reached despite pressing the accelerator, the MCOR causes problems.
  • One needs to change or repair the MCOR if no other trouble is detected for the cart’s power loss. The MCOR may have corroded over time and require replacement. 
  • A potentiometer can detect the fluctuations of the MCOR, and if the power is not as desired, the MCOR is giving problems.


Club car MCOR troubleshooting

Club car MCOR troubleshooting is a tricky job but can be done by almost all if proper tools are available in hand. It is difficult to judge when the MCOR will give problems, but the significant indications are not attaining the desired speed or jerky ride. 


Checking the terminals:

First, melt the solders and unscrew the two screws to open the MCOR. The terminals have NC and NO markings. They can be found on the sides. Continuity is found at the NC terminal at the rest position, and the NO terminals get active when the pedal or the switched is pressed. Check them


Working cautiously:

The MOCR in the club cart is delicate; therefore, I always work on them with extra care and caution. Two separate switches are connected in series and often one side break while the other side functions. If the broken side touches the NO terminal, the MOCR switches will usually work and even on or off due to the good side’s working. It is a helpless situation.


Changing the MOCR:

It is best to change the MOCR of the club class in this type of situation, and it only needs a screwdriver and a solder to fit the replacement because the broken side will never work if it touches the NC terminal. 


How to test MCOR on club car golf cart

In order to test the MCOR on a club car golf cart, you will need to perform 2 different tests. The throttle will need to be first tested, and then the On/Off switch.


First test:

The method of testing the motor controller output regulator or the MOCR is quite simple. While testing the club cart Precedent, it is done after searching the line item or the throttle.

While the cart is in a “neutral” position, pressing the pedal will gradually move the throttle from 0% to 100% and be steady.

If the readings randomly fluctuate and never reach 100%, then the MCOR is defective and needs replacement. 


Second test:

The second test relates to the two-wire on/off switch. Staying in the monitor tab, I observe the “Foot Input” with the tab down. It should be in the “Off” position. As I depress the pedal, it will turn to the “ON” position.

If the on/off positions are not working, then the MCOR on the club cart Precedent golf cart is not working or malfunctioning and needs repairing or replacement.

I also check the forward and the reverse key staying on the monitor.  


Ways to change the MCOR on the Club Car?

Changing the MCOR on a club cart is relatively easy. I always change the motor controller output regulator of my club cart without any professional help. 

  • The tools required –While changing the MCOR of my club cart, I always keep the following tools with me. They are the Ratchet, T-40 Star, 5/8 inch Socket, 1/2 inch socket 10 mm socket, and a screwdriver. 
  • Precautions –Wearing a safety glass, gloves help to stay safe. I also remove the battery terminals to avoid electrical shock. The MCOR is placed on the side of the batteries. So I remove two middle batteries to make enough space to work & remove the MCOR.
  • Changing the MCOR –Using the T-40 Star, I unscrew the board’s bolt that contains the MCOR. Noting down the wires before unplugging them helps to work swiftly as the new MCOR is fitted and connected.

    There are many wires so taking a snap with the mobile phone before unplugging them is the best option to remember. Unscrew the lead terminals. Typically the MCOR is fixed with three bolts. I unscrew them. 

It is time to mount the new MCOR after removing the old one. The process is just the opposite of unscrewing, and I follow the same. The battery terminals and other leads are fixed.

The wires are plugged-in again, and the board is placed at the same place and again screwed with the help of T-40 Star. Putting the middle batteries and connecting the terminals, the work is complete. 

How to replace MCOR on Club Car Precedent

The MCOR of the cub cart Precedent model needs change at times, and there is no need to call a professional for the job. I do it myself. With the spanners and the screwdrivers by my side, I remove the battery terminals first to avoid any electrical shock.

It is then time to remove some of the batteries to make space and unscrew the board in which the MCOR rests. I unscrew the long bolt and lift the bard out.

The MCOR on Club car Precedent is screwed on this board. Unscrew three screws that keep the MCOR in place and then unplug the wires remembering where to fit again. 

Removing the old MCOR and placing the new one, I follow the reverse process and complete the changing process.


How to install MCOR on Club Car DS

There is not much difference between installing MCOR on Club car DS and Club car Precedent. Club cart DS has MCOR1 or Carryall type controller, and the mounting is a bit different.

However, this model of MCOR is not available anymore or sparingly available. Other types of MCOR are used while charging, and it needs to change the pedal group and use a conversion kit.

With proper tools in hand, the conversion kit, the pedal group, and suitable MCOR, it is easy to mount an upgraded controller in club Car DS.


Club Car Precedent MCOR wiring diagram  

The Club car Precedent MCOR wiring diagram is available in short in the owner’s manual. However, I always take pictures of the wiring on my phone while working with the MCOR.

 I can also download the wiring diagram from the internet by going to the link however, they are not complete.

 I always follow the thumb rule “seeing believes” and refer to the pictures in addition to the owner’s manual to remember the MCOR wiring diagram.


Ernie loves documenting interesting facts about golf.

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