Why does the white 12-volt light not turn on when I power up my NOCO GB40?
If the white Boost LED (the light indicating the unit is ready to jump start) does not illuminate when you power on your NOCO…
Manuals+ Q&A
NOCO Genius Boost User Guide — questions & answers
Read product questions and troubleshooting answers linked to NOCO Genius Boost User Guide.
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Answered questions
How do I turn off the NOCO GB40 when the 75% yellow light stays on?
To turn off your NOCO Genius Boost GB40, follow these steps and considerations based on the manual: Power Button: Press the Power Button (the…
How do I use the NOCO Genius 5? I need a visual or simple overview because the text instructions are difficult to understand.
It appears you are asking about the NOCO Genius 5 battery charger, though the manual on this page is for the GB40 Boost jump…
Why is my NOCO Genius Boost showing a flashing light and not working when connected to my battery? Is the battery dead?
Hello, thank you for your question. A flashing light on your NOCO Genius Boost can indicate a few different conditions. Based on your description…
I want to use my GB40 to charge my battery. After some time, the lamp lights up green. Do I still have to wait 12 hours or is the battery fully charged when the light turns green? If you keep the manual button pressed for 3 seconds, nothing happens. Please advise for a solution.
Thank you for your question. It's important to clarify that the NOCO Genius Boost GB40 is a portable jump starter, not a battery charger.…
Why is the red exclamation mark and flashlight flashing on my NOCO Boost Plus GB40, and how do I turn it off?
The small red exclamation mark on your NOCO Boost Plus GB40 is the Error LED. According to the manual, there are two primary reasons…
Why is the Error LED blinking red on my NOCO Genius Boost when I try to charge it in cold weather?
According to the NOCO Genius Boost manual, a blinking red Error LED typically indicates that the internal battery temperature is too high. However, your…
Why is my NOCO GB40 not discharging or providing voltage to the clamps even in manual mode?
If your NOCO GB40 is fully charged and recognizes the battery but will not discharge even in Manual Override mode, please check the following…
When charging the GB40, will it discharge the car battery if left plugged into the USB port?
Recharging the NOCO Genius Boost GB40 through a vehicle's 12V USB port (using the included 12V USB charger) will draw power from the car…