It’s a golf cart owners nightmare. You plug in your golf cart to charge overnight and when you wake up, your golf cart is still dead! What have you done to deserve this treachery?
Before you just go buy a new golf cart battery charger, there are a few things you can do to check yours.
Like any other form of diagnostic testing, testing your golf cart battery charger is done in the basic series of steps:
- Confirm the issue
- Isolate the issue
- Repair the issue.
As far as testing your golf cart battery charger, the first step is making sure the problem is with the charger.
Make sure the problem really is your golf cart battery charger
There are a couple ways to do this. The first step is making sure you performed the charging process correctly.
Did you hook everything up correctly?
Is the cart and charger are both in charging mode?
Is the outlet that the charger is plugged into working?
If all of these conditions are met, then the next easiest step is hooking up the charger to a different golf cart. I know this is easier said than done. Most people don’t have a second golf cart lying around.
If it charges the other golf cart, then obviously it isn’t your charger, but it might not be a huge problem either.
Some golf cart battery chargers won’t charge a golf cart if it has fallen below a certain voltage.
Check your golf cart’s voltage and see if it is within the detection range of your charger. Get a voltmeter and read across your battery pack. It should read a couple voltages above the total pack. For instance, if you have a 48 volt battery pack, then the voltmeter should read 51ish across the whole pack, if it’s fully charged. This is also part of the maintenance you want to do on your golf cart.
Another common issue is worn out batteries. Batteries only have a lifespan of about 5-6 years at most, and usually fail sooner than that under heavy use or extreme weathers. Lastly, check all of the cables and connections on your golf cart. If your golf cart isn’t grounding properly or has a bad cable, your golf cart battery charger may not be able to work with it.
Of course, if it fails to charge the other cart, then it is most likely something on the charger side. Fear not, however. The solution may be simple, and is most likely something inexpensive and easy to replace. Before you trash your whole golf cart battery charger, make sure you can’t fix this one.
It might not be the whole golf cart battery charger
Now that you have confirmed it is your charger, it’s time to see what you can do to get your golf cart battery charger back in order. It could be a simple replacement part, or a loose wire somewhere. Before we dig into it however, let’s talk about something incredibly important.
Electricity can be very dangerous. For your safety, make sure you know what you’re doing. If handled properly, it is very easy to avoid being electrocuted, but carelessness can lead to injury, or possibly death.
A good rule is to only have the power on when you are testing it, and to completely unplug the golf cart battery charger when you’re disconnecting things or digging into any circuitry. It may take a little extra time to do those things, but your safety should be your number one concern.
Check the Timing Mechanism
The first thing to check is the timing mechanism. Your golf cart battery charger will either have a manual, mechanical timer, or an automatic electric timer. If it is a manual timer, it’s pretty easy to test.
Turn the timer on and check for power coming from the timer. If you are getting power, then your timer is working fine. With an electrical timer, you just have to trick into turning on.
The other possible problem is that your timer has failed and is leaving your charger always on. To check for this, have the timer turned off and check for power. If you’re still receiving power, replace your timer.
Check Charging Cable
If the timer is working properly, the next easiest to check, and by far the easiest to repair, is the charging cable. This usually happens when the connection to the plug or clamp has worn out.
You can check this by testing for power at the cable end, and if there is no power, check for power where it connects to the golf cart battery charger. If there is power at the charger, but not at the end of the cable, then it’s as simple as replacing your cable.
Another easy way to test a cable, if you have an ohmmeter, is to check for continuity in the cable. This is done by measuring the resistance in the cable, which should be slightly above zero. If your ohmmeter reads zero or infinity, then the cable is broken and should be replaced.
Check Fuses and Diodes
If you don’t have power at the cable connection, then don’t worry too much yet. Hopefully, it’s just a fuse.
These are pretty easy to find, and once you locate it, simply remove it and look for burnout. If you can’t see burnout, then check it for continuity on your ohmmeter again. If the fuse is broken, then you need to check a couple things before replacing it, if not, reinstall it. Sometimes this will fix the issue by draining capacitors and sort of of restarting the machine.
If your fuse is blown, then it is very possible that one or both of your diodes has gone bad. Check them both for continuity both ways. A diode is like a gate, so you should have continuity one way, but not the other.
To check for continuity, completely remove the diode from the machine and use your ohmmeter to check for resistance in the same way you checked the cable, then switch the direction you’re testing in. If both are continuous or neither are, then you have a bad diode. You may have to replace both if one is failed.
Once you’ve checked and possibly replaced your diode, replace your fuse (if blown) and check to see if your golf cart battery charger is working now. If it isn’t, then start the isolation process over, there may have been more than one fault.
If you have checked everything and all seems fine, but you’re golf cart battery charger still won’t charge your batteries, then the last thing to check is the transformer.
The transformer should be humming if it is operating, so if it isn’t humming, it’s either not receiving power or broken. Check it’s connections to the circuit board, and if all seems well, then the only real way to test it is to replace it with a known good transformer.
Unfortunately, this is crazy expensive and requires some very special soldering or replacement of an entire circuit board.
You may need to take the golf cart battery charger to a shop if you suspect the transformer is the issue. Also, this repair may be very costly and it might be in your best interest to consider a new golf cart battery charger.
Plug it in and hope it works now
Once you have confirmed, isolated, and repaired the issue, check to make sure your golf cart battery charger is working properly. If you connected everything back, and performed all necessary prepares correctly, then you should be golden. If not, go through the diagnosis process over again to find the new issue. The worst case scenario is that a circuit board has fried or that whatever repair is needed is more expensive than a new golf cart battery charger.