[4-bit Micro Computer (GMC-4)]
●The LEDs do not turn on or no sound is produced.
Potential causes of these problems are described below. Check each one carefully.
・ Ensure that the battery-box connectors are fully engaged with the corresponding circuit-board connectors. Make sure that each connector is oriented in the correct direction.
・Ensure that you are using new batteries. Replace any batteries that have run out of power. Ensure that the batteries are installed in the correct direction. When not using the micro computer, remember to always turn it off and remove the batteries.
・Check the speaker wires. If either of the wires has become detached from the speaker, rectify the situation by resoldering.
・Ensure whether the switch is set to ON.
・Check that the key sheet is not out of position. If it is, carefully realign it.
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