Another one of those questions without a quick easy answer. Everyone from a dealer to an end user wants that quick easy fix! What the industry has done for us is to create a system of easy testing, IF you have the proper test equipment. Test equipment such as programmers has been around for many years. The problem is the cost! Secondly one does not fit all. So, what is an individual to do?

First understand a controller is part of a system and does not stand alone. Secondly understand testing is done in two directions. One we call the Known Factor and one we call the Unknown Factor. So with those thoughts in mind let’s use the following example.

•           What brand of car?
•           What type of system is in the car SepEx or Series?
•           What does the car do or not do?

Let’s say for this example we have a Club Car IQ system. The car does not run. What is the first action taken at this point?

This is where we start with known factors. First we retrieve the correct wiring diagram for that system. We know the car must have a voltage supply and that is the battery pack so we confirm proper voltage OCV and load voltage. Next we confirm we have conductors for the voltage to flow. In other words check all power cables, wiring and perform a good visual inspection.

Now we look at the Unknown Factors. What we do not know at this point is what does the solenoid do (does it click)? You do not go any further with trouble shooting until we determine what is going on with the solenoid.

Solenoid clicks but does not run. Check the main contacts for being open. If open, replace the solenoid. If the solenoid checks good then we go on to motor/controller testing. Keep in mind we are testing a system so we are testing everything around the controller at this point. Too often we just jump the gun and fail to follow procedure. Be patient and go step by step to each area of testing. Now we check the motor for continuity through F1 to F2 and A1 to A2 with one each of the cables removed. If we have continuity then we can say a circuit exists though the motor. So, at this point we have checked everything around the controller, so that leaves only one thing, a defective controller.

Going back to the solenoid, it does not click. First we determine if voltage is present across the small solenoid terminals. If we read 48 volts and the solenoid does not click, replace the solenoid. If you do not read voltage we have to determine where we are losing the voltage. Check voltage at the solid blue wire. Now we move our negative voltmeter lead to battery number six negative terminal and leave the red voltmeter lead connected to the small blue wire. Activate the system and if 48 volts is not read we have issues in the key switch, tow switch to battery positive circuit. If we read 48 volts then check for a negative potential on the blue wire with white stripe. Connect the black voltmeter lead to the blue wire with white stripe and move the red voltmeter lead to battery number one positive terminal. Activate the system and if 48 volts is not present we need to check voltage potentials at the controller inputs.

This is why it is important to have the correct wiring diagram for the car! Now we have to test in-put voltages to the controller. On this particular car system the computer has a lot to do with solenoid activation. Notice that the yellow wire from the computer is connected to the foot pedal switch and to the controller. This tells us we must see 48 volts positive at pin 6 on the controller at system activation. If you do not you have wiring issues, foot switch issues, key switch issues, tow switch issues or battery connection issues. This positive voltage must be seen in order for the controller to send out a negative input to the solenoid. You must also see voltage at the red computer wire, light blue, green/white wires to and from the computer (positive). If all is well then check input voltages at pin 6,10,8, and 9 on the controller (positive). Voltages present and no solenoid activation; replace the controller. Voltage not present; replace the computer or find where voltage to the computer/controller is missing. Also confirm POT (potentiometer/ITS) voltage or resistance values. At this point you have tested the system and can now determine if the controller is defective.

Plain and simple procedure without the use of high dollar test equipment!

A large complaint from electric golf cart owners is when a golf car has been unused for several months and the owner goes to plug in the automatic charger and finds it will not come on.  They did not feel comfortable leaving the charger plugged in for the entire time since, they used the car last. But now they find out that the battery charger won’t come on.

This is one of the most common problems with electric golf cars left sitting for several months without a charger connected to it.

They appear to be dead; next a technician is called to check it out. The typical technician will check the car over and tell customers the batteries or the charger is the problem, transport the car back to the shop where they have a method of charging batteries that are under the critical 80% discharge level (70% nominal voltage level), and or checking the charger.

There are still many automatic chargers in use today that will not come on until there is at least 70% nominal charge voltage in the battery pack. That is how they were designed; this keeps them from working if there are major issues within the system. That is why they need to have a 70% nominal charge voltage to start; it was a designed safety feature. The nominal pack voltage of a 36 volt system fully charged is around 38 volts. A 48 volt battery pack fully charged would be around 52 volts. On the low end 70% (voltage) of a 36 volt pack would be close to 25 volts and a 48 volt pack at 70% (voltage) would be close to 33 volts.

The good news is that in the last five years charger technology has improved to the point where most automatic chargers only need to detect one or two volts to start a charge cycle. Also many chargers are now built with multiple fail-safe systems. Now, if the relay fails the charger will not continue to run until unplugged as some older chargers did. The problem with wet cell lead acid batteries is they discharge at a rate of 4% per week. In higher temperatures the discharge rate is even quicker. That means 16% per month. If you do the math it will only take two months and you are below the 70% nominal voltage. Newer charger technology also allows maintenance charging for storage.