discussion One Lowbeam won't light...

[dandelioneater]

I have a 2002 Nissan Pathfinder and noticed the other day that the lowbeam on the driver side was not turning on, but the highbeams were fine. The passenger-side works fine for both beams. So i replaced the bulbs, thinking that the low beam filament was dead. Still the same Problem.

Next: Checked fuses - 2x 15A fuses in fusebox attributed with headlights - both fine.

Next: Relays. There are 2 relays associated with headlights (SP-ST i think). Both 'click' when I turn the lights on. I swapped relays, same result. The wire connections appear to be secure under the relay where they terminate, but I just visually inspected them (there could still be an open somewhere there)

The bulbs have a plug with 3 conductors on them. Gnd, LB filament Votage, HB Filament Voltage. There is no 12V being switched onto the LB Filament when the low-beams are turned on.

I have limited knowledge of vehicle wiring, but I think the Lowbeam voltage wire is open somewhere. The wire colors change from the relay to the bulb plug, so I am a little stumped as to the best way to trace the wires. I do have a ohmmeter that I am competent with :biggrin:.

So to recap: New bulbs, fuses are good, relays are good, bulb plugs look good. Just the one Lowbeam on the drivers side doesn't light. Both high-beams work.

Any recommendations on what to try next before of taking it in h34r:??

 

[3.0charlie]

Use that ohmmeter, and start from the relay to the bulb, even if the cable color changes. I had to perform the exact same work on my 2004 Expedition for a backup light that would not light up in reverse - switching the bulbs right to left made no change, and I found the cut wire under the left hand passenger door threshold strip. I removed it a while back to route an amp power cable, and upon re-installing the plastic piece it cut the wire ever so slightly...

Good luck with the search.

 

[Shadowmeph]

Probably a Ground problem either the front or rear ground isn't grounded properly .

 

[dandelioneater]

thanks for the suggestions, gents. Going to get out my multimeter tomorrow afternoon and muck about under the hood some more. I think I have it narrowed down to the wires on one of the relays. I think the grounding is ok, only because if the ground wire on the bad light was open, then wouldn't the high beams not work either?

 

[Bloodystumps]

here is a schematic for your SUV

most cars the commons are ground/bad connections or the DTR module .

I am not real familiar with that particular ride so I can't think of anything off the top of my head sorry bud .

 

[dandelioneater]

thanks for the schematic. :thumb: Isn't there usually a second fuse box located inside the vehicle (under dash). According to the manual there is one but I can't locate the damn thing. I took off the glove box and didn't see anything on the passenger side.

edit: seems as though the second fusebox it is behind the coin tray on the drivers side (Not sure if there is anything in there for my situation). May be a bad light switch too....

 

[Bloodystumps]

always check all the fuses. I have had a unrelated fuse cause me grief

 

[Silent_Avenger]

Could be a wiring issue. I've seen wires corrode from simply a small hole in the insulation of the wire. If you can possibly trace back the wire to its origin and see if you're getting power at the source(usually at the relay) and if you are you will probably have to run some new wire back to the plug. Also make sure you don't have burnt terminals inside the plug because this is a common problem as well.

 

[nige]

you could ask for more help from my nissan truck club. Not familiar with the 02 pathfinders, sorry.

Canadian Nissan Truck Club • Index page

 

[Master_Shake_]

take out your daytime light control unit open it an resolder all the connections on the back of the pcb, put it back in and try it...

if that fails to fix it replace it.

source: automotive service tech...seen it and fixed it before.

this will help you