Why doesn't my left tail light work on my 2000 Grand caravan. I have Changed the bulb. That didn't fix the problem.
As a general rule, your new bulb should be in good working order. Just to make sure swop it with the matching bulb on the other side of the vehicle which you know is definitely working. If this bulb now operates in the first lamp assembly you now know the problem. Turn your ignition on off when you check the bulb for working as some vehicles use this as a reset, also check any line fuses. If it does not work, then unplug the lamp and check out the wiring for voltage supply and earth with a voltmeter. Check the terminals of the lamp plate for corrosion or heat damage and rectify as necessary. Check the lamps bulb plate for a good circuit(s) through its conductor bars. They sometimes seperate and go open circuit. Finally double check that the bulb is fitted correctly. It is not too un-common for the bulb to forced round into its holder, the bulb contacts then being out of position to make contact. From experiance my first actions would be be check bulb, check supply and earth, check bulb plate.
It could be due to bad or corroded connections at tail light plug. I thin you should check the connections the fuse. May be the two filaments are separately fused.