We've had intermittent reports that a headlight was out on one of our Jettas. Both have aftermarket "eurospec" headlamps with fog lights from ECS Tuning. They claim to be Hella lights, but could well be forgeries.
Today, I finally caught the light being out and decided to replace the bulb. When I pulled the bulb I noticed that the connector was slightly melted at the low beam ground terminal (the one between the two parallel side terminals) and that both filaments seemed to be intact. I confirmed that the bulb as good and tightened up the flag connector on the melted terminal.
The lights are working again, but I'm wondering. Are there other possible explanations of the heating / melting besides a loose connector?