A Z06 External Battery Tender Port--Another Approach

I was inspired by Ray Kawal’s approach to making an externally accessible, but hidden Battery Tender port.  While Ray used items he had laying around, I was not so fortunate, and had to round up my materials.  This may have too much detail for some, but I thought I’d err on the side of more rather than less.  In any case, read all of this before beginning!!

The real challenge I faced was finding a panel mount port that was small enough to allow easy access to the space just to the right of the right license plate light.  I also wanted something which could only go in one way so I wouldn’t have a polarity problem.  I looked at many different possibilities and finally settled on an XLR panel mount male plug which I fastened to my bracket using pop rivets.  Note in the picture below that there is a small vertical slot in the plug which, along with the three pins will only go in one way.

But I am getting ahead of myself.  First I had to make a bracket to hold the male XLR plug.  To get access, you remove the inner right hand tail/stop light using a #15 Torx bit; I would suggest you put some tape ( I used blue painter’s tape because that is what I had handy) on the taillight lens to protect it while you are removing/replacing it.  Then pulling on the tab where the Torx screw was, you can remove the taillight.  At this time it is easy to separate the tail light housing and put it somewhere it won’t be damaged.

I then removed the right hand license plate light (use the #15 Torx bit again) and separated the housing from the light.  Using a small piece of stiff cardboard from the back of a writing tablet (see to the right), I traced the outline of the opening and the holes where the screws secured the right license plate light housing.  After a lot of checking and rechecking, my resulting template looked like this:

I found some sheet aluminum (0.10”) that would be stiff enough but not too thick.  Place Scotch Magic tape on the aluminum and trace the outline of the template and the holes to be drilled in it on the tape.  (See below).  Secure the aluminum sheet to something solid (I clamped the sheet to a radial arm saw table with a scrap piece of wood to protect the aluminum).  Using an electric scroll saw with a medium or fine metal cutting blade, cut the aluminum sheet.  Smooth the edges to protect you fingers and the car.

Then drill 9/64” holes for the screws securing the license plate light housing and the panel mount (assuming you’ll use 1/8” pop rivets).  Along the way, continue to keep checking the fit of the bracket in YOUR car so you don’t have to redo the bracket a second time.  When you are done, your bracket should look approximately like this:

In assembling the pieces to go on to your bracket make absolutely certain that you have everything correctly postitioned.  Drilling out pop rivets is not hard, but it’s not the most fun activity either.  Lightly screwing the license light housing may help in ensuring correct positioning.  If you decide to do this, DON’T screw the screws in all the way.  Otherwise you may have to get slightly larger screws. 

Wiring: Since I don’t really understand electricity, I tend to build very robust things when electricity is involved.  I used the largest wire size (#14) that could be soldered into the solder pots of my plugs.  Although I may not often actually plug in a 10 amp charger, I wanted to be able to do so if the battery went completely flat.  I bought separate wires five feet each, of 14 gage red and black wire to go from the male plug into the battery compartment.  To connect to the battery, I found 2” “Claw Clips” at Radio Shack.  In addition, as Ray Kawal did, I also included a fuse in the hot side, just in case.  For use with the battery tender, I plan to use 4 amp fuses; with the charger, I’ll switch that to a 15 amp fuse.

To connect to the male plug on the car, I found an XLR female L-plug which has a small latch.  That latch really gets in the way, so I removed it.  Even with the panel mounted male plug oriented just right, it was too tight a fit.  So I ground off a portion of the of the plug’s shell too. (See below)

For the wire that connects the above plug to the Battery Tender or charger, I used 14 gage red/black twin lead that I got from our local electronics store.

Here are a couple of pictures of the L-Plug loosely installed on the back of the Vette. 

You can see the ground off portions of the plug’s shell in both pictures.  Normally this would be fully plugged-in and you would not see it. 

 Looking at the battery in the car (below), you can see the fuse housing on the hot (Red) wire that is underneath the car’s large hot lead (in the top/center of the picture).

Then because I wanted to make certain that I didn’t accidentally short circuit the battery by having the + & - leads touch, I build a stand so that the plug's leads could be clamped on one side of the threaded bolt and the charger/Battery Tender’ leads clips to the other side.

Well, that’s it.  If you have any questions, you can email me at smy850@comcast.net

The above is Steve's installation which came out really nice.  The tricky part is finding a connector that will just fit in the license plate light cutout area.  Once you find a connector small enough to fit, make a plate to mount the connector.

You can email me at ray@kawal.net