240z Holley RetroBright LED Headlights - With Jumper Wire Conversion

[Datsunpowers]

  For a couple years I have researched LED headlights for my 71 240Z. I wanted a headlight that had a great beam pattern and looked like a stock headlight. The headlight I choose was the Holley Retrobright LED headlights in Modern White from Headlight Revolution. Here is the link Holley RetroBright Classic LED Sealed Beam Headlights | 7" Round (headlightrevolution.com). The Headlight Revolution website has great information and testing results on LED headlights.  The good news is the headlight fits and plugs into the stock headlight bucket without any modification. I have used these LED headlights for several months now and I really like them. I now enjoy driving the car at night and see the road and deer in front of me for a change! They are pricy, but you get what you pay for here.

 

With these LED headlights the current draw is significantly lower than the stock headlight current draw. This means I can use the stock 240Z wiring harness by swapping two wires in the headlight switches. This swap changes the polarity needed for the LED headlights. I was going to use the Hella H4 headlights and did test them, but it would have required a new headlight harness to handle the increased current draw.

 

Here are the different headlights I tested and amp draw.

 

Here is the 240Z light switch modification that’s required to switch the headlight plug polarity for the LED headlights. This wiring modification is completely reversible. You will need the following materials.

 

Materials needed:

1.       ATO fuse holder with wiring extension

2.       15 amp ATO Fuse

3.       14 Gauge jumper wire

4.       2 Female bullet connectors

5.       2 Male bullet connectors

6.       Voltmeter or Test Light for testing

 

LED Jumper Wiring Modification with ATO Fuse Holder

 

Wiring Procedure: (Pictures below)

1.       Remove the steering column cover.

2.       Unplug the Black wires from the Lower Headlight Switch and the High Low Switch.

3.       Unplug the Red wires from the Upper Headlight Switch and the wire that runs to the headlight fuse block. This is the red common connection to the LH and RH Headlight fuses.

4.       Connect the Red wire from the Upper Headlight Switch to one side of the ATO fuse holder. Note: you will have to extend the wires on the ATO fuse holder, so you can access the fuse holder with the steering cover on.

5.       Connect the Black wire from the High Low Switch to the other side of the ATO fuse holder.

6.       Insert a 15 amp fuse in the new ATO fuse holder. This is now your headlight fuse for both LED headlights. The headlight 12v power comes from the headlight switch.

7.       Make a 2” long jumper wire with a male and female bullet on each end.

8.       Connect Black lower headlight switch female bullet connector to the male jumper.

9.       Connect the Red from the Common LH and RH Headlight fuses male bullet to the female jumper wire.

10.       Now you have switched the polarity at the headlight plugs. To test your connections you can use a Voltmeter or Test Light. At the headlight plug you will have one common ground and 12v+ for the high and low beam. 

11.       Install the new LED headlights and adjust the beam pattern per the FSM. This so you get the best beam pattern and you will not blind oncoming traffic.

12.       Reinstall the steering column cover very carefully. (The plastic screw holes in the cover like to crack and strip out very easily).

 

LED Jumper Wiring Modification with ATO Fuse Holder Installed

 

Upper Headlight Switch

 

High Low Beam Switch

 

Headlight plug electrical outputs before modification

 

Headlight plug electrical outputs after LED wiring modification

 

240z FSM Headlight Wiring Diagram

 

Holley Part Number

 

 

71 240z Holley Retrobright LED Headlights

 

These Holley LED headlights bring the headlights up to modern standards with a classic look. The have a great beam pattern that really lights up the road when you're driving and don't blind other drivers. They come in different colors and the LED bulbs are replaceable. I choose the Modern White color vs. Classic White.  They really have worked well for me so far! 

[DuffyMahoney]

Thanks for the write up, I would have never thought it would need a harness

[Mike Mileski]

How did you know that you needed to change the polarity? Did that information come in the instructions with the Holley LED headlights?

 

Mike Mileski

Tucson, AZ

[Datsunpowers]

Mike the headlights didn’t have any polarity instructions with them. They did work out of the box in my 69 Camero. When I plugged them in my 240z they didn’t work. This is when I discovered the wiring polarity on the 240z is a non-standard H4 plug. With incandescent bulbs polarity doesn’t matter, but with LED lights it does. Here is a standard H4 plug and the non-standard H4 plug on the 240z. Switching two wires at the headlights switch corrects the polarity for a standard H4 plug. I am sure this applies to other H4 LED bulbs, but I don’t have experience with them.

 

[Mike Mileski]

Wow, I'm always learning something new. Thanks for the info.

 

Mike Mileski

Tucson, AZ

[MinneZota]

Hi there, I am running the Holly Retrobrights on my 1978 280z. Currently I have lowbeams and high beams at the same time, but if I switch to just low beams, I have nothing. I also do not have running lights at the headlights, just high beam. So here I am trying to construct your creation! I am running into a few issues. The Red 12v wire from the top switch seems to be 10 gauge wire with matching 10 gauge bullet connectors. How did you get these two to connect with the connectors for the 14 gauge wire connectors?

Edited May 13 by MinneZota

[MinneZota]

 

[Datsunpowers]

MinneZota, I am not sure what you wires you are showing in the picture, so it hard for me to determine what was cut. From the instructions above you do not need to cut any wires or connectors for the swap. You must make the ATO fuse jumper wire and the small jumper wire pictured in the instruction above. By using the two jumper wires you made this allows you to plug them in the existing harness and swap the main red and black wires pictured. This changes the polarity for the LED headlights to work correctly. You can message me I can walk you through it.    

 

   

[MinneZota]

Thanks for the reply! I apologize, I should have included more info. The bigger wire (on the left) is the 12V wire coming from the top lighting switch. The reason it’s cut is because when I went to disconnect the old bullet connections, it must have overheated in the past with the halogens and melted the connection (so it needed a new connector anyway). The wire on the right, the smaller one, is the extension wire from the ATO fuse holder, I removed the connector to show the size difference. I would absolutely love some help with this if you’re willing. I can message additional pictures and videos when I get home to give you a clearer view of my situation. 

Edited Monday at 09:01 PM by MinneZota

[Datsunpowers]

Here is a quick way to check the polarity and the high low switch. Use a voltmeter and ground the negative side of the meter to the car ground. Take the positive lead and touch it to the center of the high low switch. You should have positive +12V with the headlight switch turned on. The low beam wire (Red/Yellow) is at the top and the high beam is (Red/White) at the bottom. The positive +12v will toggle between the two when the turn signal switch is toggled. I enclosed the switch and labeled the different terminals. If that is correct check the polarity at the headlight plug. You should have one ground and +12V at low beam and +12v at high beam.

 

One other thought is check the fuse block and make sure the two headlight fuses are good. You will have one for the left and on for the right light.

 

Hope it helps.