Outer Limits 4x4 Board

ok i bought all proper wires and relays to do a upgrade on my headlight wiring in my sierra so i can have good quality driving lights.

the high beams are brighter but the low beams (driving lights) are a fair bit dimmer. i have no idea why this is.

they are narva 55/60w h4 bulbs. i also tried pluging in a whole other sealed buld that i had as a spare and same result. when i plug in the stock loom back in the lowbeams are brighter in both.

i thought i might be a crappy earth so i only used trigger wires ( + and - ) straight from the battery and not from old loom but still same.

tried another relay and still same.

its wierd as high beams are a little brighter than before but lows are dim and i used duel core, one to high and one to low. even swiched them around and same.

ok then since so one knows yets maybe we can break it down.

if i put a tester on the end of the wiring what are the volt and current readings i should be getting on the upgraded wiring compared to stock?
mainly i mean which should be higher, im assuming the upgraded and if im getting a better reading shouldnt that produce a brighter light? how does it work?

Hi mate,

This is just my understanding of it but you replace the wiring loom with a higher rated loom. You replaced the bulbs with standard wattage globes.

The readings at the bulbs would be the same 12v or 14.1v depending on what you are doing.

What rating is the new wiring loom? if its up around 100 or 130 watt then go get some higher powered globes and see how that goes.

Paul

Replacement looms are typically designed to reduce the voltage drop in the wiring, so you end up with higher voltage at the globe. So you really need to measure the voltage at the globe in both looms (factory & aftermarket) and compare.

I would guess that the duller light has lower voltage at the globe, which isn't what you're supposed to have with a fancy new loom. So it would be a matter of measuring voltage at every point you can get to, to see if you can find where it's "escaping".

yes that makes sense. ill have to go buy a voltmeter on the weekend then.

i also tried it with another relay and swapped wires over and globe is still dimmer.

im getting phillips 55/60w xtreme globes now which can run on stock loom but if i figure out this new loom then they will be better still.

here they are
http://www.powerbulbs.com/product_detail.asp?prod=43

check the earths on the high beam

the earths on the high beam are in the selector on the dash, dont know where its connected to the body thou but im assuming all have to same connection to the body somewhere, and the relay earths are good. im buying a mulitmeter this weekend finally and a good set of bulbs i can use with stock wiring.

i have the same problem on my 4runner, it is producing 12.4v at globe or 14.3v when running, it also had a week low beam and great high beam. i put 90/120watt globes in and they are heaps better

sweet so the lows are well bright with the 90/120 setup. at least i got the option there if i want to put in brighter bulbs.

currently i have both looms still there so all i have to do to swithch over is unplug one set and plug in another.

so judging by your reading u are getting the right wattage at globes but for some reason the normal globes lows arnt bright. wiered

thats right, it does nt sound right but thats the way its working out

Just a thought. When your lights are on low beam, have a close look at the filaments - have you got one or two glowing?