If you were looking for an answer that was either "yes" or "no" you may be disappointed.
A compass on a boat can be affected by any local magnetic field created on the boat that is sufficiently strong to cause the effect of the Earth's magnetic field to be altered and for the compass to swing off the magnetic field of the Earth or "magnetic North."
Electrical currents flowing near a magnetic compass may affect the compass indication of magnetic north. To test, observe the compass indication with all electrical power shut off to the electrical devices you wish to test for interference with the compass. Then apply electrical power to the devices under test, one at a time. Observe the compass for any change in reading when electrical power is applied.
To predict the outcome is difficult to do with certainty.
There is a prior discussion on "Magnetic field from DC current" which can give you some guidance. SeeMagnetic Field From DC Currenthttp://continuouswave.com/ubb/Forum6/HTML/003731.html
Test before drilling a big hole in the dashboard.