Headlight Relay Install

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1980 -1985 Vanagons

Parts Needed:

  • 2 - relay sockets, standard automotive type that have a tab for screwing to a flat surface.
  • 8 - spade, female, relay socket, terminals for 12 ~ 14 ga. wire
  • 2 - 40 amp relays, four pin, VW/Audi #141 951 253 B
  • 1 - double terminal end extender
  • 8" - #14 ga. wire, stranded copper, yellow
  • 8" - #14 ga. wire, stranded copper, white
  • 16" - #12 ga. wire, stranded copper, red
  • 24" - #14 ga. wire, stranded copper, brown
  • 2 - spade, female, terminals for 12 ga. wire
  • 6 - spade, female, terminals for 14 ga. wire.



Installation Procedure for 1980 - 1985 Vanagons

New relay kits are now completley pre-wired with all four wires to the relay installed. Please follow the following directions to install one of these new kits. Please read ALL instructions below to understand what you need to do before beginning.


  • 12 gauge yellow wires from both relay terminals #30 goes to position # 7 as described below.
  • 12 gauge yellow wire from first relay terminal #87 goes to fused position #4 as described below.
  • 12 gauge yellow wire from second relay terminal #87 goes to fused position # 6 as described below.
  • 14 gauge wires from both relay terminals #85 with uninsulated spade connector goes to ground as described below.
  • 14 gauge yellow wire from first relay terminal #86 goes to wire removed from fused position #4 as described below.
  • 14 gauge yellow wire from second relay terminal #86 goes to wire removed from fused position #6 as described below.


Remove the Vanagon's fuse block from the firewall under the left-hand corner of the dash by removing the large phillips head screws on the mounting bracket. On the reverse side of the fuse block you will find at fuse position 7 a spare male terminal end, on the fused side of the fuse, where you can pick up the necessary 12 volt fused power supply for the headlights. Fuse 7 should have a 16 amp fuse. Test with a 12 volt light tester to make sure there is 12 volts present when the ignition key is in the on position. Using a double terminal end extender connected to the free male terminal, connect one end of each of the two 8" red 12 gauge wires with a female terminal end securely crimped on each end, to this 12 volt power supply terminal. Crimp on a female spade relay socket terminal end on each of the opposite ends of the two red 12 gauge wires then plug them into the relay sockets so they line up with position 30 of the relays.

NOTE - For Safety reasons, you should disconnect the negative terminal from your battery after doing the test for power at the terminals if you feel unsure of yourself working with the electrical circuits involved.

Next, take two 12" 14ga. brown wires and attach one 14 ga. female spade terminal end to each of them. Then attach one female spade relay socket terminal end to each of the other ends. Locate the round grounding block on the firewall above where the fuse block was located. There should be some empty male spade terminals. Plug the brown wires on them. Run these wires to the relay sockets and insert the two female spade terminals with the brown wires attached into position 85 on each relay socket. While there, locate the two brown ground wires from the headlamps which are terminating together in one connector. If there are more than one pair you can determine which pair are for the headlights by turning on the headlights then removing one pair at a time until the headlights go out. Cut the connector off and attach one female spade connector to each wire and reconnect each one to an individual terminal on the grounding block. This will improve the return path of the electricity from the headlamps.

Next, looking at the rear of the fuse box, the side that was against the firewall before you removed it, find at fuse 4 the single 12 gauge yellow w/black stripe input wire that goes to the two fuses of the low beams of the right and left headlights. This wire should have 12v power when the low beam headlights are on and low beam headlamp fuses, #3 & #4 fuses, are removed. Remove this wire from its connector, cut off the terminal end and crimp on a new female spade relay socket terminal end then connect it to one of the relay holders at position 86. Take the 8" yellow 14 gauge wire and crimp on a female spade relay socket terminal and connect it to the same relay socket at position 87. Crimp on a female spade terminal end to the opposite end then plug it on the terminal on back of fuse 4 where you previously removed the yellow w/black stripe wire.


Next, looking at the rear of the fuse box, the side that was against the firewall before you removed it, find at fuse 6 the single 12 gauge white input wire that goes to the two fuses of the high beams of the right and left headlights. This wire should have 12v power when the high beam headlights are on and high beam headlamp fuses, #5 & #6 fuses, are removed. Remove this wire from its connector, cut off the terminal end and crimp on a new female spade relay socket terminal end then connect it to the other relay socket at position 86. Take the 8" white 14 gauge wire and crimp on a female spade relay socket terminal and connect it to the same relay socket at position 87. Crimp on a female spade terminal end to the opposite end then plug it on the terminal on back of fuse 6 where you previously removed the white wire.

Now, push the relays into the relay sockets. Then secure the relay holders to the fuse box with tie wraps.

Now your done and ready for a test. Start the vehicle and make sure the charging indicator light is out. Turn on the head lamp main switch. Activate the dimmer switch to see if you have high and low beams operating. Test the voltage at the headlamp plug if you wish, it should now be higher. If everything is satisfactory replace the fuse block on the firewall being careful to position all the wires so that there is no strain on any of them. Enjoy your new headlamp power !

If you decide to use higher wattage bulbs in your headlamps after installing the relays, you may find the fuses will burn out. If this is the case then you can install higher amperage fuses in the fuse positions for the headlamps. Use the next size higher amperage fuse. Do not go higher than necessary to keep your new bulbs from burning the fuses. Usually one size larger is needed and sufficient on the high beam circuit only.

Ken Lewis write up here

Alistair Bell's diagram of his install on an '82 diesel westy. Separate power feed line added in this case.


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