It seems the most common mistake made in connecting a new battery is to connect the positive and negative wires to the wrong terminals. You can't always depend on the color of the wires to indicate which is the positive and negative wires. If you are sure it is connected right, you will probably want a voltmeter to trouble shoot the wiring.
Check the voltage at the battery, positive post to negative post. If ok there, move along the wires, both positive and negative, one step at a time and check for voltage. When you no longer have a voltage, that's where your problem is.
If you don't have a voltmeter you could use a light bulb with wires connected to it, but a light bulb doesn't indicate polarity.
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