Repairing an Ebike - start with the batteries

netrate

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I had read that if one battery goes, replace all four. The bike I have is in parts, but I want to test out the batteries. Any advice? 2010 Gio.
 
Get a dvm, some alligator clip leads, and a load resistor. For a 48 v 840 wh battery I use a 10 ohm 1050 W resistor. For other voltages you would use other resistors.
Hook up the dvm parallel to the load resistor. Do the test outside, if there is a fire you can burn your concrete step. Connect the battery and see how long the battery maintains normal charged voltage at 5 amps. I had two **** batteries collapse to 7 and 11 volts during this test. My good one I disconnect it after an hour, no problem.
Resistance & wattage would vary for other voltage batteries. 10 ohm would only load a 12 v battery to 1.2 amps. No test at all. Flashlight batteries would pass that test.
 
I am quite new to this, so thank you for taking the time to answer my questions.

They are indeed 4 x 12V so 480. On my voltage meter I don't have a 12V setting so I don't want to ruin it (if that is possible).
The batteries are good according to the person I purchased this from, but I will get to the batteries later.

I am going to move onto the charging unit first.
When the charger is PLUGGED INTO THE WALL - BUT not into the ebike, will the charger light up or does the fan on the charger run?

I am not sure if it is a faulty charger. I might to get that first.
 
Modern chargers are switching supplies. Cheap switching supplies require a load on them to function. In fact operating without a load can damage some switching supplies. Ensure a load is on the supply, like a battery, then check to see if the voltage on the battery increases when the charger is plugged in the AC supply.
My supply shows green LED when AC is on it but the battery is not. Then the LED goes red when I connect the battery. The fan runs when the LED is red. When the battery voltage is up to that shown on the charger label, the LED goes green again and the fan stops. My "48 v" charger stops at 53.6 for Lion batteries.
Voltmeters measure voltage up to the maximum name of the scale. Thus you would measure a 12 v battery on a 15 v , 20 v or 25 VDC scale. 50 v scale would work but would be harder to read.
 
I've got the lid off the charging unit now and plugged it into the wall for about 15 minutes but there is nothing. No light, no fan.
When plugged into the GIO, the same occurred. No light, no fan.
I have unplugged the charger and felt electronics to see if they are warm, and they are stone cold.
 
I will try putting the voltmeter on the battery when it is plugged in. Does it matter which battery I pick of the four? All of the batteries are currently attached to each other.
 
The voltmeter is not enough load to activate a battery charger if it is looking for a load.
You can test any battery you wish. You can charge any battery you wish. Batteries below 11.5 v probably need a charge. Batteries 12.5 v & above probably don't. You may need cables with alligator clips to charge individual batteries if the charger is a 12 v charger. They have large alligator clips at the auto supply. You may need solder and a propane torch to install one on a wire. I got an 80 w electric iron to do it but it was iffy.
 
I tested all the batteries, they were all above 12.5. I plugged the chargers in after I did the testing and retested the batteries again and there was no change. Was that what I was supposed to do?
 
Here is the charger
20220302_153400.jpg
 
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Ok some success. The batteries work. After fiddling with the wires under the seat, it powers on. Moves forward, left turn signal works, headlight does not, right turn signal doesn't work. Not sure if the charge will work until this charge wears down to nothing. There is some wiring work I'm going to have to look into. Does anyone know where I can get the manual online? I have searched for 2010 Gio but the models I have seen don't look like the one I have.
 
That is a switcher supply. Unless the power cord is bad, they are not generally repairable by amateurs. I can't do it.
If you want to check 12 v batteries something cheaper than a 1000 w resistor can be purchased. A headlight will draw about 6 amps. A windshield defroster will draw about 20 amps.
 
I am going to see what is working tomorrow (lights). The bike drives forward, which is a plus so I know the batteries are at least powering the motor. The left turn signal is good, but not the right.
I am looking for the manual on this bike to get a better sense of what is working and what isn't. I wouldn't want to attempt to repair the charger - it is better for me to spend the $40 and get a new one. That way I know it is working. BUT I still do not know if it is charging or not until the batteries wear down some.
Do you know where the Model number is located usually on Gio ebikes?
 
Here are some pics
 

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You shouldn't need to pay $40 to buy a small charger for a 12 v lead acid battery. You should be able to buy generic chargers for about that. Only if the charger works on a stack of 4 batteries would there be anything special about it. 48 v lead acid chargers would have a different cut off voltage than more common 48 v lithium ion battery charger.
 
Yeah, I am not sure what to look for on Amazon, but I will start the search tomorrow. But before that, I just realised I have an outlet tester that I can try on the female end of the charger when its plugged in to see if current is getting through. I will try that tomorrow.
 
Ok tested the charger (female end} with my electrical outlet tester and the tester does not light up. Outlet tested, works fine.
I think the charger might be caput.
 
An outlet is AC, charger output is DC. I have no idea what you electrical outlet tester is, but a chance it won't work with DC.
 
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