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Discussion Starter · #1 ·
Update to my post 11 days ago…. with picture.

Good news! The wire gauge on the factory wires is 17 gauge. That is a wee bit larger than 18 gauge that I said they were. Why does this matter? For any length of wire, there is a 'design standard' for how much current that wire diameter can carry. The National Electrical Code design standard is no more than a 3% voltage drop (VD) for a single circuit. For a branch circuit, which is what the headlights on each side of the car are 4 bulbs on one ground wire – including the Amber lights, the rule is 5% VD. If the high beam lights are on, 18ga wire would exceed 5%. That is not just an automotive standard, its household, AC/ DC… everything.

The owner's manual of newer cars all suggest not adding any additional items to the electrical system such as lights and big stereo equipment. All the wiring is the minimum required to meet specification and low cost while trading some efficiency for low weight and cost. It's ok to add things, just check the wattage or amperage of the item and make sure the circuit is not overloaded.

Here we are just looking for comparison showing all the variables. The final take away below, is noting the voltage drop to wire size and the wattage increase of the High beam bulb'

1 headlight (no Amber lights) – Package Information. 12 volts, 55 watts = 4.58A calculated, 17ga, 5ft = VD 1.92% /14ga, 5ft = VD 0.96%.

1 headlight (no Amber lights) – Package Information. 12 volts, 65 watts, 5.41A calculated, 17ga, 5ft = VD 2.2% /14ga, 5ft = VD 1.13%.
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Here is the calculation for the High beam upgrade where we have 2 high beam 65 watt bulbs on one side of the car (including Amber lights 8.3w+5w). - All 1 ground wire -12 volts, 143 watts = 11.91A calculated, 17ga, 5ft = Voltage Drop 5.01% or 0.60 volts /14ga, 5ft = Voltage Drop 2.5% or 0.3 volts.

Note the voltage drop with the amber lights 5.01% is at the limit of 5%. This is why it is important to Math out any upgrade. But you can probably do the bulb upgrade without changing the ground wire. I replaced the ground wire to 14 ga. and cut the voltage drop in half. But I only upgraded both headlights ground wire, I left the Amber light on the factory ground.

So I cooled my jets a little and simply replaced the h11 connector with a H9 connector with 14 ga wire. I also put the High and Low on a dedicated 14 gauge ground to the chassis. They originally have a single ground for all 4 lights in each side housing directly to ground. I left the 2 amber bulbs on the factory ground, and then cut the 17 ga wire inside the headlight housing and then added a 14ga directly to the chassis ground. I did pull up the fuse box and identified the + wires to the 2 halogen bulbs in the housing, but didn’t feel it worth the effort get into the loom jumble of wires.

Here is an excellent 14 gauge pigtail connector. Dorman 645-993 $5.74. (Rockauto) Cut off the connector end that is not needed, solder it in or crimp. NOTE: Do not buy -- Any connector part not listing the wire size. It is likely 18 ga. and will have much thinner connection metal. Junk!

The OEM connectors have a thicker metal connector, as does the Dorman part.

Here is a pic of the lights on the garage door. The right one is still the 55 w bulb, then with both 65w. (Hmmm… Interesting that the new bulbs have a bit of light scatter, perhaps that is why there is a black coating on the tip of the bulb). After I adjusted the bulbs for optimum view on the road - but also to keep them out of oncoming drivers eyes – the difference is really like Night and Day, and with the 65w fog lights on too, it all just fills in nicely! Highly recommend it!
Goggles.
Light Car Automotive lighting Automotive design Hood
 
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Thanks for the write up! I've been trying to fix my headlights to pass inspection the last couple days and I'm running into some trouble. What I thought was a bad ground was actually just me wiring my new connectors wrong. So I cut the factory ground line. Then I attached it to a new wire and ran it to a new ground spot. Now, the side that was messed up is working. But the passenger side that was working perfectly before, the high beam and turn signal don't work. Do you think it's because I changed the ground to a different gauge wire?
 

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Thanks for the write up! I've been trying to fix my headlights to pass inspection the last couple days and I'm running into some trouble. What I thought was a bad ground was actually just me wiring my new connectors wrong. So I cut the factory ground line. Then I attached it to a new wire and ran it to a new ground spot. Now, the side that was messed up is working. But the passenger side that was working perfectly before, the high beam and turn signal don't work. Do you think it's because I changed the ground to a different gauge wire?
Personally I would say it would not. I would guess that it could be poorly grounded, poorly crimped or something more of that nature rather than the gauge of wire. If you have access to a multimeter or continuity tester you could check if the ground is good . Hope you can find and fix it
 

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Discussion Starter · #4 ·
Personally I would say it would not. I would guess that it could be poorly grounded, poorly crimped or something more of that nature rather than the gauge of wire. If you have access to a multimeter or continuity tester you could check if the ground is good . Hope you can find and fix it
Thanks for the write up! I've been trying to fix my headlights to pass inspection the last couple days and I'm running into some trouble. What I thought was a bad ground was actually just me wiring my new connectors wrong. So I cut the factory ground line. Then I attached it to a new wire and ran it to a new ground spot. Now, the side that was messed up is working. But the passenger side that was working perfectly before, the high beam and turn signal don't work. Do you think it's because I changed the ground to a different gauge wire?
Hi Blvckhvrt, boomer is correct - but before getting the meter/test light out, I would check the fuses. Each side is fused separately, and if I recall High and Low are also fused separately. When testing, think systematically. Random spot checking always get ME confused - prolly cuz I'm dyslexic! Wire gauge will not be a problem if it is larger wire.
 
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It seems like it was some kind of fluke. When I went back to fix the problem it was gone. 🤷🏽‍♂️ I seem to have a new problem that's kind of strange. For some reason the brown wire on the drivers side seems to be hot. I believe this is supposed to be the front parking light, the one the lights up your side marker. But for some reason, on the drivers side it's also lighting up the turn signal solid amber, making the turn signal not blink when I turn them on.


Then again, it could be that the turn signal is SUPPOSED to be lit up when it's in park, which would mean the passenger side isn't lighting up when it should be. Even if that's the case, the problem still remains with the drivers side light bit turning off while driving.
 

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Discussion Starter · #6 ·
My car is not apart anymore so I can't check any wire colors for you.
When you say a wire seems to be hot - do you mean has +12 volts power, or the wire temperature is " Hot! ".

I just tested the operation of the parking lights. The side marker and parking lights are always on at the same time (I believe that means 1 wire feeds both bulbs with a jumper). When the turn signal is activated, the side marker is still on solid and never blinks, the parking light blinks brighter. The Parking light / Turn Signal uses a 2 filament bulb. It has a dim filament for parking light, and a bright filament for the turn signal. If the bulb gets installed 180 degrees rotation the parking light will always be too bright, and it will be difficult to see the dim filament blink.

Hope this helps!
I am wondering if there might be a problem with the switch on the steering column.
 
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