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Bugeye Wiring Diagram - First Draft

David_Doan

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Bugeye Wiring Diagram - Second Draft

Update 5/22/14:

I learned a few things since the 1st version. Something was screwy on my car before that it would only run if the key was “on” and the light switch was on “S” or “H”. I thought this was a feature of the switch, but my ohm meter proved me wrong. The owners manual also says that only the ignition key is required to start and run. Given this, the circuits are now broken down as follows:


  1. Headlights
  2. Brake lights
  3. Horn
  4. Lighting
    • Parking Lights
    • Gauge Lights
  5. Key Switch
    • Ignition
    • Fuel pump
    • Flashers
    • Wipers
    • Heater
    • Tach
    • Fuel Gauge
  6. Power Port


Lights, brake lights, horn, aux. power port are always available. The key switch enables everything else.

New version can be downloaded here: https://doanfamily.net/blog/2014/05/22/re-wiring-take-2/


After a lot of procrastination, I finished the first draft of the wiring diagram for my car. I'm doing the new harness from scratch to accommodate:



  • Negative Ground
  • 3 wire alternator
  • Electric Fuel Pump
  • Relays and fuses
  • Electric Tach
  • Front Tilt

What I have done so far is the "electrical" layout. I still need to work on the physical wire run locations, wire sizes, fuses, etc.

PowerPoint and Pdf versions of what I have so far can be dowloaded here: https://doanfamily.net/blog/2014/05/20/re-wiring-take-1/

I would appreciate opinion, critques, and criticism. My goal is to only do this once and hopefully save someone else some time if anyone else wants to re-wire their car.

Thanks,

David

P.S. If you were previously subscribed to my blog, I have lost my list. I you want to get email updates, please go to: https://doanfamily.net/blog/ and click subscribe. TY
 
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I would appreciate opinion,

The relays on the stop lights and the ignition might be overly complicating the wiring? Unless the ignition really uses more amps than the switch will handle over the long run adding a relay is just one more point of failure.

Heater fan?

Also the little Bosch relays are pretty robust but I've had problems in the past with the headlight hi/low method shown. You can eliminate 1 relay by using 2 SPDT relays connected to the DIP switch, one for right and one for left (low on the NC). It's not much fun to go to high beam only to find that you get dark instead. Separating the right and left means that both relays would have to fail to get the same result.

One other point, probably not really relevant to a bugeye but worth considering, the relays with the built in suppression diode cost a little more but just might prevent some future problems if the electronics are upgraded later.
 
Heater is gone...

I did the headlight setup like that because I'm not using the floor mounted DIP switch. Since the heater is gone, the heater switch with the "H" on it will now enable the high beams.

I agree on the relay possibly not being needed for ignition and brake lights.
 
You need one for wipers. Big drain there on that old switch.
 
David, it certainly looks like you are on the right track but I would agree with eliminating some of those relays as really not necessary and just another complicating factor. Having done a similar project for my Prefect, and it all works by the way, I can appreciate the task you have set out for yourself as well as the effort already put into it. If interested, https://enfoprefect.org/cars/Prefect_Wiring.html is a link to the description and diagrams of my wiring job.

Sorry, I can't remember how to make a UBB link. I'll try to fix it as soon as I can figure it out or some kind person jogs my memory.
 
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I've had problems in the past with the headlight hi/low method shown. You can eliminate 1 relay by using 2 SPDT relays connected to the DIP switch, one for right and one for left (low on the NC). It's not much fun to go to high beam only to find that you get dark instead. Separating the right and left means that both relays would have to fail to get the same result.

I read this again. I understand the potential advantage of left and right SPDT relays, but you would still need a 3rd relay in front of them to turn the lights on/off, then use the DIP switch to to move the left/right relays from low to high beam.
 
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Thanks David. I fixed the link. Basil's magic again makes it pretty much too easy.
 
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