I need to put the battery in an '88 NA convertible. Which wire is the ground (-) and which is the positive. I have two terminals coming out of the harness together. One with a long wire which is black with a yellow stripe, and one shorter which is two black going into the battery terminal. It looks like the yellow stripe is the positive by orientation of the battery but the electrical diagrams label the plain black as positive.
I didn't find the answer on a quick search, I don't have the owners manual and the electrical diagrams don't give the colors of the ground.
Thanks, I don't want to start out by frying anything.
Russell

 

It would be nice if you indicated the year or series of your car. On my S5 FC, the short black cable is positive and the longer black with the stripe is negative. The battery should be positioned in the battery box as so. The terminals will be closes to the fender and the negative post will be on your left when viewed from the drivers fender. So, with the battery positioned in that manner, the relative lengths of the cables will make it obvious which is which.

 

Is it just me or did he already state the year of his car? If his is an '88, then that would be an s4, in which case it might be a little different.

 

Huh, yes he did.

 

positive is the rear connection, and negitive is the front(closest to the driver headlight).
my negitive wire was replaced with a red wire, so you cant always go by color.

 

S4 or S5 the long black wire with the stripe is the negative. The short black wire is the positive.