Blue LED on 5005 base board

The system I have developed is based loosely on the Wisblock tracker example. In that, the green led is used to indicate transmission activity and the blue led just flashes continuously. The code that controls the green led is straightforward, but I cannot understand how the blue led is controlled - I’d like to use it for something else.


Hi @Alangward ,

What specific WisBlock tracker example do you use?

You should be able to control the Blue LED via


It could be the blue LED is setup as BLE indicator. In that case the blue LED blinks while BLE is active and goes on permanent when a phone connected over BLE.

The function to switch on/off the BLE blue LED function should be somewhere in the BLE initialization.

Search for Bluefruit.autoConnLed

// BLE LED function off

// BLE LED function on

Well I turned that Blue LED (for BLE indication) off by changing this line of code :

Go to


and remove or comment out this line of code :

line# 367 : Bluefruit._startConnLed();

I don’t know if there’s a convenient way of doing this on the application level, rather than modifying the library.

Can you give me a link to the example code you are using?
It should be possible by just calling Bluefruit.autoConnLed(false); before you start advertising.