[sailor]

Hadn't heard of electrically heated windscreens B4, on "our side of the pond" they are only used for rear glass.

On those, the electrical connectors to both sides are fairly "obvious" and usually located centrally on each side. Be VERY careful if you disconnect such for testing (hold the base contact onto the window when pulling the connector) because it is VERY easy to pull the connector off the window & break it in the process!!

Testing by probing the connections is preferred as a result, since replacing /repairing windows gets a bit pricey!

Luck!

P.S. - when testing, one side should show continuity to ground while the other would show battery voltage when actuated.