Solution: Replace batteries.

Cause: Smaller batteries - Sometimes batteries (often cheaper brands) are too small and they can fall out from in-between the terminals when the RCX is moved.


Solution: Replace with new, higher quality batteries. Load all the batteries into your RCX and before you replace the cover, lightly shake the RCX to see if the batteries fall out. There should be firm enough contact between the batteries and the conductive plates in the battery chamber of the RCX to hold the batteries in place while shaken.

Cause: Improperly-sized rechargeable batteries

Solution: Replace with a different brand of rechargeables. For more info, see the Knowledgebase question, "Can I use rechargeable batteries in my RCX?"

Cause: Unevenly charged rechargeable batteries