My friend just bought the european code (E-Code) OEM headlamps for his '02 'vert. It is a new lamp/housing assy, with single high/low H4 bulb instead of the american two lamp system. What is the easiest way to combine the two plug system into the new one plug H4 system?

 

Get the "Y" wiring harness adapter from LAPD (a Corvette Forum vendor).

Plug and pray. :smash:

 

You can make up your own harness using heavy gage wire and the correct size *blade* fittings to attach to the bulb. Or, perhaps you already have the three-prong harness that comes with the kit, but don't know where to connect the "other ends" of that harness to the car's circuits.

Anyway, looking at the back of the bulb:

The vertical prong on the left goes to ground. Any ground. I went to a large bolt that is on the chassis just under the headlamp assy. Or, you could splice into either BLACK wire on the existing headlamp harness. Either black wire....you don't need both. They all go to a grounding attachment connection, just behind the headlights, directly to the chassis.

The vertical prong on the right goes to the GREEN headlamp wire.

The horizontal prong on the top goes to the TAN headlamp wire.

These Green and Tan wires, on both sides of the car, are the high and low lamps, but I forget which is which. No matter, though.

I suggest soldering the headlamp harness to the green and tan wires......I don't fully trust crimp connectors on these high-current draw circuits.