Project Lexus SC300 Road Racer: Part 9 – Begin Rewiring at the… Back?


Tom is using a small butane soldering iron with a torch attachment to shrink W5 glueline.

W5 is yet another type of heat shrink tube. It comes from Sumitube, but is similar / comparable to Raychem SCL. It is really hard and stiff, and has a glue liner. It is great for splices. With a 3:1 shrink ratio and a lot of stiffness, it actually helps to pull the wires on both sides of the splice towards one another, adding further to the mechanical stability of the splice, as well as providing an environmental seal.

You want to cut the glueline here to be long enough so that, when recovered (shrunk) it does not expose any of the conductor surface. In this manner the glueline also acts as an insulator, but does a much better and neater job than electrical tape.

Now that the factory wires are properly prepped, which one does what? The tail lamps on Project SC300 are not 1992 lamps, but actually come from a different model year. Unfortunately for us, that meant that the wiring colors listed in the 1992 SC300 factory service manual were not the same as the wire colors on the car. What to do?


Here we have a Milwaukee 12 volt battery.

Cars use 12 volt electronics. This battery is 12 volts. Perhaps we can make something work here…


What if we just crimp some .250” tab connectors onto some wires…


Voila! A portalbe 12v power supply for testing small circuits!

I wouldn't try to start the car with this bad boy, but it's more than enough to power up lights and small motors.


Let there be light!

In a few moments, we were able to figure out which wire powered which bulb, so then we knew how to pin out our connectors on the tail lamps. And, of course, we wrote it down so that we would be able to know what happened later. At this point we were basically ready to put pins on wires and start assembling connectors.

But how does one properly put the pins on the wires and assemble the connectors? Glad you asked.

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