GMC c3500 reverse lights

1998 GMC C3500
140,000 MILES • V8 • 2WD • AUTOMATIC
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FRANKS_CL
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What could be making the reverse lights not work on a 1998 GMC c3500 van/bus? The light bulbs are fine, the sockets are fine, I even changed the neutral safety switch like autozone said. We were told it could be the back up sensor on the transmission but where exactly is that located on the transmission?
Nov 20, 2010 at 1:46 PM
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JDL
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The backup lite switch is for manual tranny. The neutral switch is for the automatic. Do the turn signals work? Did you check applicable fuses?
Nov 20, 2010 at 2:36 PM
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JDL
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Also, check voltage and ground at the bulb socket. In reverse, the lite green wire is voltage, the black wire is ground.
Nov 20, 2010 at 2:39 PM
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FRANKS_CL
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Yes the turn signals work and all fuses work. There is only one wire going to the socket and its black. Also the running lights above it work and only have one black wire going to them. The reverse light socket reads 1.3v.
Nov 20, 2010 at 2:48 PM
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JDL
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database, Mitchel, shows that diagram for backup lights?
Nov 22, 2010 at 9:57 PM
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