E-code is a shortened form of European code. Volvo produced for use where that code is extant could have the all glass lights, as shown in that picture. Volvos for the North American markets got either a 4-lamp sealed beam layout, or - for the 1986-1993 240s - a single H4 bulb behind a plastic lens.

The plastic lens goes yellow, leaks, and looks (IMHO) ugly. Many owners in the US want or have the all glass E-code lights.

For you, if you have only one bulb on each side, and the lens is glass, you have the E-code type. Unfortunately you cannot upgrade to E-code, as we can.

The other posts mention a relay system, and I think one of the sites referenced, will show the wiring diagram.

Summarily - a relay is placed so that the wire now going to the headlight goes to the relay coil instead. Then a heavy wire from the battery to the headlight is installed. Thus when the relay closes the headlight gets all the power it can use. Voltage is not reduced by going through a long bunch of thinner gauge wire. Some have reported 15% improvement.

Good Luck,

Bob

:>)