What was found
WINDOW HEAT 2L EICAS MSG DISPLAYED. A WEIRD ODOR WAS APPARENT IN THE COCKPIT THEN C/B TRIPPED FOR 2L. NO RESET ATTEMPTED. INVESTIGATED & FOUND LOOSE WINDOW HEAT CONTROL THERMOSTAT WIRING & "WINDOW HEAT 2L" MESSAGE ON EICAS. LOOSE WIRING MAY HAVE CAUSED ARCING & ODOR. THE LOOSE WIRE WAS REATTACHED TO COCKPIT WINDOW. "WINDOW HEAT 2L" MESSAGE WAS GONE, AND A/C RETURNED TO REVENUE SERVICE WITHOUT FURTHER ODOR OR WINDOW HEAT PROBLEM.