hi there this is my first post i am new to this forum. the car is 2000 gmc yukon slt please i need help. i replaced both alternator nd battery . first it was the battery . car turned on after i replaced battery but (when i went to tighten bolts) i accidentally tocuhed positive terminal with it connected to battery with a wrench to the body frame. After that , the car seems to have an electrical issue. i have checked all fuses (in side engine compartment and driver under dash) all fuses are ok . Relays seem ok.. I checked VOltage at the cig lighter (4.5 volts) I dont know what went wrong i need help