Q: 'My golf cart battery charger hums and clicks, but the needle isn't moving at all. What is the most likely explanation for this type of behavior from my golf cart battery charger?'
A: There are several reasons why the unit may be acting this way. As such, there are a number of things to rule out in order to determine what the underlying problem is. Then we can fix that factor and resolve the entire issue.
First, check the needle gauge (the ammeter). This unit may be working perfectly, with the exception of a failing ammeter, so this is a good thing to isolate first. And the easiest way to determine if the ammeter is working correctly is to pass current through it using a voltmeter. Using a voltmeter will show whether the golf cart battery charger's ammeter is working or not.
Next, if you're having trouble getting your golf cart started and you think it's related to the battery; let's get a 'battery reference voltage' reading from your golf cart battery. This is the amount of voltage that is present in the golf cart battery when it is not under any load. For example, a 48-volt golf cart battery should have a reading of about 48 volts, and a 36-volt golf cart battery, a reading of 36 volts.
To take a battery reference voltage reading, make sure the battery charger is unplugged from the golf cart, and that the key is turned off. Then touch the positive probe of your voltmeter to the main positive (+) terminal, and the negative voltmeter probe to the main negative (-) terminal of the golf cart battery.
If the battery reference voltage reading increases significantly this means the charger is good and the ammeter is not functioning correctly. If the battery reference voltage reading does not increase this means there is a problem with the golf cart battery charger itself.
Q: I left my golf cart battery charger unattended for a long period of time and now it does not turn on. What should I do and why did this happen?
A: Most new electric golf carts have a 'tow' or 'maintenance' switch that is a type of kill switch inside the battery compartment. If one does not put this switch into the 'tow' or 'off' position while the golf cart is charging, the golf cart's batteries will be drained at a rate of about one million volt per day due to the controller's requirement for the slight amount of power.
After a few months, the golf cart batteries will become 'dead' or weak. The newer kinds of electronic golf cart battery chargers have to sense a particular amount of voltage coming from the golf cart batteries before the battery charger will come online and charge the battery.
If the golf cart battery charger does not sense the batteries, this is most likely because the battery voltage has dropped below the amount required for the golf cart battery charger to read and recognize as batteries that need to be charged.
One way to remedy this problem is to use an older type of non-electronic 36 or 48 volt battery charger. This will very likely bring the voltage of your golf cart batteries back up to the required charge that the newer battery charger is looking for. Many times this 'critical charge' amount is about 31 volts. Of course this varies from model to model.
Also, it is worth noting that if you opt to use one of the older battery chargers, you may need to use some type of adapter in order to be able to plug the older charger into the car. Once everything is set up, it shouldn't take any longer than about thirty minutes for this older style charger to fully charge the golf cart battery.
Yet another option is to charge both of the batteries at the same time with a 12-volt charger. You would connect the batteries in a series and attach the battery charger as well. Once the critical required level of charge is reached, then you can use the newer, electronic battery charger as normal.
Q: My golf cart battery charger won't turn off when it's finished charging the battery. Is this something I should worry about?
A: First of all, there are a number of reasons this may be happening. In automatic chargers, there could simply be a bad battery that can no longer hold a charge. This means that the automatic battery charger may not ever sense the cutoff level of charge coming back form the golf cart battery, which marks the point at which the charger is supposed to switch off.
This problem can also be caused by a faulty circuit board in some battery chargers. For the most part though, automatic battery chargers have at least one circuit board dedicated to sensing this type of cutoff point and reading of charge.
Basically, if there is any reason why the board may not be reading the appropriate cutoff charge, it will fail to turn off because it doesn't believe that the golf cart batteries have bee fully charged.
Another reason that a golf cart battery charger may not turn off is that its timer has gone bad. Many older charge s have manual timers in place and estimate the amount of time it will take to charge a battery. If these are not functioning properly, the charger may very well just keep running.