I have been doing a lot of LED retrofit for different owners. That is what they can afford these days.
There are two common problems that I run into:
Bad grounds
Wrong polarity
It sounds like you have a mixture.
With the economy still in the tank, I have been doing a lot of these conversions. It barely pays enough to get out of bed, but hey, that is what's left.
Matt
Matt & Mary Colie
A sailor, his bride and their black dogs (one dear dog is waiting for us at the bridge) going to see some dry places that have Geocaches in a coach made the year we married.