I have a 1999 ezgo txt golf cart and want to know what type and size 12 volt battery to install?

Some help in the link, but you may need dealer service to diagnose.

https://www.google.com/search?q=1996+ezgo+txt+golf+cart+buzzing+sound%2C+no+go

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loose power connection or bad ground somewhere. get a little metal wire brush (or several of them), disconnect battery, and disconnect ground and power wires (keeping track of them), and start brushing them, then re-attach and test

It may need a repair

There are a ton of them available, apparently:

https://www.google.com/search?q=1999+TXT+EZGO+golf+cart+controller&oq=1999+TXT+EZGO+golf+cart+controller&aqs=chrome..69i57.1143j0j4&sourceid=chrome&ie=UTF-8

Never had a ezgo 3 wheeler to work on before but sounds interesting. If this is an electric cart then wire ground to a negative battery that gives 12 volts from where positive is connected. If gas cart wire to frame or neg post of battery.

Does your controller have a 6 pin connector on the top? If it does then only 4 pins are wired. Pins 1 and 2 are the throttle, pin 3 is reverse and pin 4 activates the controller.
First I would check the batteries under load. then check voltage from main negative battery post to pins 3 and 4. Should get approx. 15 volts going to the ITS throttle and other pin should get 5 volts at full throttle. If you get no voltage at either pin then probably a bad controller. Go to buggiesgonewild.com and search for wiring diagrams, they have a few for download.

Service manuals are sold by EZGO but expensive. You might download some wiring diagrams from fsip.biz and buggiesgonewild.com.

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