the following was courtes= y of ken wilford.. i was just cleaning out my files and thought some of you = may benefit from this.   i did this to my van and now i can run 80= /100w H4's in there without melting the headlight switch..   big i= mprovement!  
enjoy..
chris
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How to Wire Headlights with Relays for Higher Wattage Bulbs

Parts you need to do this:
2- 40 Amp Relays
4- Rolls of Different Colored 14 gauge wiring
Box of Female Spade connectors (blue)
2- Fuse Holders for 16 amp fuses
2- 16 amp fuses
2- Ring connectors for battery connection

Run two 14 gauge feed wires from your battery to the fuse panel area. =  Crimp a spade connector to each wire.  Hook the power wires to one side= of the 2 fuse holders.  Now make another wire for each fuse holder and ru= n this to the power side of the relay (pin 30 on the relay)-(I would use red= wires for this to indicate they are power wires).  The relays that I woul= d recommend would be the 40 amp relay that is used on the Vanagon.  These = are part number 141 951 253B.  Now you want to label the two relays: High = Beam and Low Beam.  Now you go to fuse panel.  Here you will see the fou= r fuses at places number 3, 4, 5, 6.  Number 3 is low beam left and 4 is l= ow beam right.  Number 5 is highbeam left and 6 is highbeam right.  You = want to unplug the two main feed wires to the four fuses (lowbeam should be = yellow with a black stripe and highbeam should be white).  Plug these powe= r supply wires into the number 85 pin on your two relays (be sure to plug th= e proper wire into the properly labeled relay).  Now you want to make up t= wo ground wires for the relays as well.  I would use a brown wire for thes= e as this is typical ground color for VWs.  Plug one end of the ground wir= e into the number 86 pin on the relay and the other end onto the ground star= connector located behind the fuse panel and to the left.  Now you want to= unplug the four connectors from the fuse panel that feed the lights.  The= se should be white for highbeam left, white with a black stripe for high bea= m right.  Splice these two together by cutting off the two connectors and = crimping both wires into a single female spade connector.  Now do the same= thing with the low beam wires (should be yellow for low beam left and yello= w with a black stripe for low beam right).  Now plug these wires onto the = relay pin number 87 on the corresponding relay.  You should be done.  Te= st your lights and then secure everything in the dash taking care to tape up= any exposed connections with electrial tape.  

Thanks,
Ken Wilford
John 3:16
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