one low beam wire dead, fog light tapping, trouble shooting?

doing a project, have one low beam wire dead, other low beam wire works, both highs work

long story, but fogs worked at one point, now one side low beam doesn't work, but both highs work...

put in some fog lights on my fiance's nissan murano today with HID bulbs..

setup is as follows:

OEM replacement housings to fit into factory spots (murano S did not come with fogs but have the cutouts for them)

DDM tuning slim ballast with bulbs

idea was to have the fogs come on with the low beams only.

so the wiring was setup to have a relay to trigger the ballasts.

30=power
87=ballasts
85=ground
86=low beam trigger

the headlight harness has three wires going into it, red, green and black. using a volt meter i was able to to determine that the red went to low, green to high and black was a common ground.

so i spiced the 86 wire into the red wire. after wrapping things up, the lights worked fine. lows on, fogs on, highs on, fogs off.

then after the vehicle sat for a few minutes while we ordered some food, went to turn the vehicle on to pick up the food, fogs didn't work and the light that i tapped into didn't work.

the driver side low works, pass low not. both highs work and all of the running lights work.

so i took the volt meter to the wire, and nothing.

when i first had the relay setup, i had the 86 and 85 reversed. could this have fried the wire?

right now i have the relay hooked up how i've seen models online and now tapped into the running lights and is working fine, but the pass low beam still does not work.

can you fry a wire? i doubt there is a separate fuse for one wire, so a fuse is not the issue. been running around in circles on this one.

any ideas?


thanks ahead of time..

 

85 and 86 are just the relay coil... polarity doesn't matter.

 

There probably IS a separate fuse for that one low beam. As for why it blew? Could be a bad relay (not likely) or a mishap with your wiring.

 

that's what i thought...thanks for the reassurance


it just activates the magnet and figured it didn't matter which is which...either way it would activate the magnet

 

think so?

hmm...guess i'll have to go through and actually eliminate that from the equation...

 

I know the Tacoma has separate fuses for each side, and I believe even for hi and lo beam. So four fuses total for the headlights.

 

seems like overkill...did not know that...didn't really seems to make sense to have separate fuses so i dismissed it off the bat...

 

checked two fuse boxes and nothing is blown...idk if they have more than that...one inside and one in the engine bay is what i saw

 

found the third fuse box....yes third...

turns out you were right...there is a separate fuse for each hi/lo right/left beam

problem is, damn near impossible to pull any of the fuses! fcking nissans!

but gives me a place to start tomorrow once i figure out how to have smaller hands and pliers...or find me some better fuse pullers...

thanks for the help...i'll report back tomorow

 

Can almost guarantee its just a fuse. If you have a voltmeter like you said, you shouldn't have to pull the fuse out to visually inspect it. Besides, I've had fuses look fine but get bad, and vice-versa. Recommend just using your meter to test the fuse while its connected.

As for the reason why the fuse blew, this is my concern....

By "wrapping things up" what exactly do you mean? Did you solder and shrink wrap your low beam tap, did you use t-taps or 3m quick connectors, or did you just twist the wires and put tape on them or a wire nut? I suspect poor wiring as the reason for your failure. Also check the connections at the relay. Be sure no pins are touching or arching, and make sure everything is weather sealed in the engine bay. Recommend using split loom as well for heat protection.

Good luck.

 

thanks man. always uses wire connectors,crimp then wrap the connections in electrical tape after. I spliced into the low beam, which I hate doing because it never seems to be a good connection but space is tight. going to check the fuse this morning and check the relay again like you suggested.

 

it's alive!


had a dead truck in the morning to throw into the mix as well...we knew the battery was going, and the stress of working on the electrical (yes the battery was off when i worked on it) and all the testing (never really ran the truck while testing) probably put it over the edge..

pulled the fuse this morning and found the answer to the headlight...blown fuse

they do have a separate fuse for hi rh, low rh, hi lh and low lh...so replaced the fuse and headlight works..

also move the trigger wire to the running lights which draw less amps and make that connection better than the original one off the low beam...HIDs work perfect now

i know most states like to have the fogs go off with highs, so down the road i may have to move this around, but for now the fogs come on with the running lights...which looks good btw...and funny how the HID fogs drown out the headlights..HID ftw! haha

thanks for all the input guys