If you connected the battery wrong, it will blink red then green alternating colors. This red-green blinking means you hooked up the battery "polarity" wrong.
My Battery Tender flashs red to green? - Amazon.com: Customer ...
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A green light flashing on the battery charger of your golf cart usually indicates the charge level of the battery. Short green flashes mean the charge level is below 80%, where long flashes mean the charge level is above 80%. If it is one solid green light it indicates the golf cart's battery is fully charged to 100%.
Why Golf Cart Charger Lights are Flashing (Red/Green/Yellow)
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