Hello, and welcome!
It would be helpful to know what type of safe you have and the model number. Most of the safes questions we get are about Sentry safes, so I will give you information about that, and if you have a different kind of safe, please let me know and I will be glad to continue to help.
The first thing to try, is changing the batteries. When the yellow light comes on, it usually means 'low battery.' Make sure to use only alkaline (never rechargeable) batteries and if you've never changed the batteries before, please ask me for instructions and I'll be happy to provide them. If you have a Sentry safe, just let me know if you have a rectangular or circular keypad. Also, check the battery holder for any corrosion and if you find any, you can clean that out with a Q-tip dipped in rubbing alcohol.
Please let me know what happens when you change the batteries and/or if you need instructions to do so.
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