Harness: CRUISER'S MOSTLY RENIX TIPS

HEADLIGHT HARNESS UPGRADE

NOVEMBER 17, 2015 SALAD 48 COMMENTS


It’s easy to install a supplemental headlight harness.

From the factory, the voltage to the headlight bulbs travels from the battery, through connectors, inside the cabin, to the headlamp switch, and then back out to the lamps via undersized wire and more connectors. It’s not uncommon to find only 10.5 volts at the lamps.

The supplemental harness is installed so that it provides battery voltage to the lamps and is just triggered by the factory wiring. The result is about 35% brighter headlamps and headlight switches that don’t melt and burn out.

Here’s a link to a harness on ebay: http://www.ebay.com/itm/CERAMIC-H4-H...-/330997592807

Absolutely plug and play:

• Remove grille and headlamp bulbs. I fed my harnesses from the passenger side starting between the battery and the back of the headlamp housing, over to the driver side.
• Plug the driver side bulb into the new harness.
• Attach the new harness’s ground wire under one of the small bolts on the radiator support after scraping the paint off under it.
• Attach the harness to the existing harness behind the grille working toward the passenger side.
• Plug the new harness plug into passenger headlamp.
• Plug original headlamp plug into receptacle on new harness.
• Attach the ground for the passenger side just like you did the driver side under a radiator support bolt.
• Attach relays with provided bracket on the passenger side inner fender.
• Connect power wires to battery.

I might also offer to check the headlight connectors. After the upgrade I didn't have high beams. A closer look at the connector (you still need to use a connector for the switch) was in poor shape, and red wire just plain snapped while handling. Tossed old connector and wired directly.

BTW measured the voltage coming out of the the "upgrade" and it's 14.2 volts.

Measured the voltage coming out of the repaired OEM circuit and it's...


...14.2 volts.

Seems to be less of an "upgrade" and more like a "bypass".

That isn't the right test. You would need to do a voltage-drop test between the battery and the headlamp connector while the headlamps are on (current flowing). Another good test would be an amp clamp to measure current at the headlamp connector (with lamp on).

Results may or may not be impressive, but just testing unloaded voltage won't show you much (its like measuring the water pressure on your garden hose, but not caring how big the diameter of the hose is or how much water is trying to actually flow).

Great, makes much more sense. Now only getting 11.8 volts from the old side.

Is the general consensus to just upgrade the harness and put in better bulbs when LED units are not being considered?

I did my harness a while back and it did increase voltage to the bulbs, but not by a great amount, my HL switch must be in a reasonable condition. Even with the harness though, I still have many points where I question if my headlights are even on. My light units still look clean and reflective on the inside but with it being a RHD, most options I find in terms of unit replacement wouldn't pass a UK MOT inspection.

After inspecting the headlight sockets for corrosion I suggest buying a new MOT approved headlight and install it. That allows you to do a side by side comparison. If the new lamp is an improvement then it is a safe bet the issue is due to aged bulbs. Even though the reflector looks good if your headlamp is similar in construction to US original equipment lamps I believe there is a halogen capsule within that contains the filament and halogen gas. With time the filament degrades and clouds the inner capsule with the result being less useful light produced by the headlight assembly. You should not have to spend a lot to get a decent improvement.

After you have improved your headlights take a look at other critical bulbs such as those for stop and turn lamps. I expect you will find the bulbs darkened internally and dusty on the exterior. Replacing them will improve their visibility.

If by that you mean they are a sealed unit and the bulb is not changeable, my ones can swap out the bulbs so the issue is not with the filament burning out or the glass being clouded over.

As I have the headlight harness, the connectors to the bulbs are brand new so no issues there. Prior to fitting the harness I had renewed the connectors on the original loom too.

I have however found these on eBay, has anyone heard of "Crystal headlights" before?
eBay

I'd pass on those.

IIWY I'd follow Jordan's advice. Measure the voltage under load. It seems to me that if you're running +/- 14.0 volts any lamp would provide sufficient light, and a heckuva lot more than if they're so dim now you're wondering if your lights are even turned on.

I got the H4 housings from Amazon along with the wiring harness and Hella 80/100w bulbs and it was a huge improvement.

How do you like those bulbs? I ordered a set from Amazon, but they sent me the 55w/60w bulbs my mistake, so I never reordered. Are they worth it? Keep in mind I have 2 100w Hella Rallye 4000 lights, so it's not like I can't see at night.

It's more when in lit areas that I question them being on. However, if I can improve them I'd be happy.

I really like them, they are the brightest headlights I have ever had. I am not a fan of LED or HID so if you want bright halogens they are the best I have found so far.
Here is a comparison to the stock headlight on the left.

Just a quick update, I did buy these and I've got to say there is a noticeable improvement outside of well lit areas. I can see my side of the road easier when against oncoming traffic and when on hi-beams, the road is very well lit.