Minn Kota battery indicator not working

[samt]

I have an 80lbs MK terrova bow mount that the button on the base of the unit to test the state of battery charge left has stopped working. Can anyone give me an indication on any way to do some basic troubleshooting to identify the cause and if it is repairable or just order the new part now. I have to order a new depth collar anyway so will add another part to that if required.

Any help is appreciated as i have never had one of these apart before.

Sam.