You are correct, the outer shell of the socket is negative (-, vehicle
ground, black wire).
The center prong is positive (+, red wire).

Dunno the consequences of wiring backwards... on DC motors, this just makes
'em spin the other way, don't know how much your pump mechanism will like that.

Tim

At 11:09 PM 3/9/2004 -0500, you wrote:
>I broke the end of the plug on a 12v air pump that I carry in case my
>Vanagon picks up a nail and  a slow leak.   I got a replacement from
>Radio Shack that has spring loaded wholes for the + and - wires.  From
>looking at the insides of the broken plug which has a short red wire
>inside, it appears that the positive wire goes to the center prong of
>the plug and the negative wire to the side contacts.
>
>Is this correct?
>
>Hopefully I won't do this, but what would be the consequence for the
>pump if I accidentally wired it backwards?
>
>Sam
>
>--
>Sam Walters
>Baltimore, MD
>
>89 Syncro GL
>85 Westy Weekender
>84 Vanagon, original owner, soon to be retired, just too many problems
>
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