Need help on installing a CD/Stereo in my VW Van

[puerco-bellies]

One of my speakers had blown so I figured I may as well update my stereo/cassette to a CD/i-pod capable unit in my van. It is a 1987 Vanagon Syncro. The stereo out on the old factory installed unit had separate grounds for each speaker.

The front speakers are working perfectly. When I pulled the left rear (I simply unscrewed it from the backing) I noticed it had two grounds. I tested the left with both grounds joined to the negative connection and the speaker did not work properly. I retested the left speaker with just one ground and it worked perfectly. The right rear did not work properly with the ground that was routed to it. I routed the "extra" ground from the left side to the right rear and tested it and it did not work at all. This is only the second time I've ever installed a stereo, and I am totally stumped on what is the problem.

Any ideas on what the problem might be?

[TrogL]

1. Sometimes they ground through the chassis

You may be connecting ground to ground instead juice to the speakers.