Dual Voltage Tail Lights

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=90 BGCOLOR="#006633" TEXT="#F7F7FF" bgproperties="fixed" background="079005a0ddvuru.png"> <div> <A HREF="http://www.vernco.com/index.htm" TARGET="_top" TITLE="http://www.vernco.com/index.htm"><U><B>home</B></U></A><B>     |     </B><FONT SIZE="5" COLOR="#FFCC66" FACE="Arial" ><B>Vern</B><B>co.com</B></FONT></div> <div> back to<B>  </B><A HREF="index.htm" TARGET="_top" TITLE="Chasing Sparks"><U><B>Chasing Sparks</B></U></A></div> <bR> <div> <A HREF="http://www.vernco.com/id173.htm" TARGET="_top" TITLE="http://www.vernco.com/id173.htm"><U><B>Site Map</B></U></A></div> <div> </div> </td> </tr><tr> <td valign="top" width=150 BGCOLOR="#669966" TEXT="#080000"> <div> <B>Dual Voltage Tail Lights</B></div> <div> <A HREF="id250.htm" TARGET="_top" TITLE="Turn Signals"><U>Turn Signals</U></A></div> <div> <A HREF="id254.htm" TARGET="_top" TITLE="New Wiring 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front wheels track better, put the transfer case in neutral, and that is about it.  (Leave the transmission in high gear to prevent damage caused by oil starvation at the pilot roller bearings between the input and output shafts.)  My <A HREF="http://www.vernco.com/rearaxle3/" TARGET="_top" TITLE="http://www.vernco.com/rearaxle3/"><U>full-floater conversion</U></A> for the rear axle makes flat-towing even easier.</div> <bR> <div> One of the biggest problems was what to do for tail lights while under tow.  Some folks use temporary auxiliary lights like you'd see behind a tow truck.  The lights have to be set up and taken down each time, and then must be stored while the Jeep is being used.</div> <bR> <div> If I had converted the Jeep to 12 volts, the tail lights can be isolated with diodes to operate like trailer lights.  These diodes are readily available at RV supply houses, designed for a motorhome towing a car.  However, the 6 volt system had a lot of appeal to me and I didn't want to lose that.  I went through lots of mental aerobics trying to figure out how to operate the 6 volt tail lights behind a 12 volt tow vehicle.  Through the use of dropping resistors and diodes, it was possible but not very practical.  The dropping resistors would have to dissipate as much energy as the 6 volt bulbs, meaning a lot of heat.  I had even come up with a way to operate the 6 volt bulbs in series, meaning no resistors, but it got WAY too complicated.</div> <bR> <div> Like all projects that get too hairy, it went on the back burner.  Then it hit me.  One of the previous owners had installed different tail lights.  These are oval shaped flush mounted lights like seen on big trucks.  A rubber grommet hold them in place in the sheetmetal.  I was not especially crazy about them, but it would have taken a lot of sheetmetal work to fill the holes so they stayed for now.  As a bonus, they are fairly well protected from the abuse that often claims protruding tail lights:</div> <bR> <div> <A HREF="id251.htm" TARGET="_top" TITLE="Tail light cover on"><U><IMG SRC="3937da70.jpg" border=0 width="125" height="167" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> With the red cover removed, here is the secret of 12 volt tail lights for flat-towing.  Right below the normal bulb holder, I epoxied a second socket in place.  Since the tail light housing is plastic, ground wires must be used.  The #1154 bulbs are wired to the stock 6 volt system.  The #2057 bulbs are wired to a separate cable that connects to the tow vehicle.  The cable is safely tucked inside the frame rail and secured as needed with clamps.  An appropriate length sticks out at the front with a connector on the end.  The tow bar has several cable stowage clips for when the Jeep is being driven.  The 6 and 12 volt systems are completely isolated except for a common ground wire.  The bulbs have dual filaments, allowing each to operate as combined Turn/Stop and Marker lights.  Since the 12 volt light is slightly off center, its reflected intensity is slightly reduced but not enough to worry about.  These bulbs are available at any good auto parts store:</div> <bR> <div> <A HREF="id252.htm" TARGET="_top" TITLE="Tail light cover off"><U><IMG SRC="395af9c0.jpg" border=0 width="175" height="156" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> I wouldn't do this conversion to a rare stock tail light.  However, many Jeeps sport aftermarket replacements.  As long as there is room inside the housing, any type of tail light could be converted like this.  I wouldn't recommend adding these flush style tail lights due to the large hole that must be cut in the sheet metal.  Should you desire to use this style, many of these lenses are sealed.  When the bulb burns out, the entire light assembly is replaced.  Signal-Stat makes one version that features a removable cover and replaceable bulb.</div> <bR> <div> The long gone stock tail light would have had a clear lens on the bottom to illuminate the license plate.  I found an aftermarket license plate light and removed the single socket inside.  New sockets were carefully formed from brass tubing and soldered in place.  The cover for this light, not shown in this picture, has an opening on the bottom.  This Jeep had a lot of extra holes here and there, but I think this was where the stock tail light would have mounted.  I did not have to enlarge the existing hole.  If you have a protruding tail light with a clear lens on the bottom this extra license plate light would not be needed:</div> <bR> <div> <A HREF="id253.htm" TARGET="_top" TITLE="License plate light"><U><IMG SRC="397af560.jpg" border=0 width="175" height="86" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></U></A></div> <bR> <div> The bulbs for the license plate light are small in order to fit side by side.  These are not readily available at an auto parts house.  Try a local electronics supply house.  For an online source, check out Newark Electronics.  Click <A HREF="http://www.newark.com/NewarkWebCommerce/newark/en_US/support/catalog/productDetail.jsp?id=50N8126" TARGET="_blank" TITLE="http://www.newark.com/NewarkWebCommerce/"><U>here</U></A> for the 12V #756 bulb.  Click <A HREF="http://www.newark.com/NewarkWebCommerce/newark/en_US/support/catalog/productDetail.jsp?id=50N8060" TARGET="_blank" TITLE="http://www.newark.com/NewarkWebCommerce/"><U>here</U></A> for the 6V #47 bulb.</div> <bR> </td> </tr></table></body>