Ford 2003 Mustang Workshop Manual page 3750

Tin the bus bar repair area with solder.
4. CAUTION: To prevent overheating the rear window glass, remove the soldering gun
as soon as the solder flows.
Preheat the rear window glass in the area to be repaired using the special tool and solder the
terminal to the bus bar.
5. NOTE: Turn the heated rear window switch ON for five minutes prior to the final inspection of
the repair.
Apply rear window defroster repair to the area as needed.