How to fix?

You could at least give a brief description of what kind of fault the unit has

Pat--Car Audio Repairs
November 2016

Replace capacitor C22 2uF 15V

Good Luck...
November 2016

You start by finding out the make and model. Then you work out exactly how to describe the problem.

Then you do a Google search or two for that make, model and problem.

Then you find a dedicated forum for equipment from that manufacturer and see if there are any specialists who know.

Then you ask in a general forum like this, in the hope that a wider audience may throw something up.

Anon
November 2016