maybe a dumb question...but Im not an electrician.. [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: maybe a dumb question...but Im not an electrician..


steakman
06-07-2009, 10:40 PM
OK. I have dbl fog holes either side of new bumper. Went and bought 2 sets of 55w fogs. I installed them in paralell I believe it is called. My thinking was that if I put them in series, I would be getting 55W total ea side and not 55w per lamp. However I now blow fuses.

Question: Is the OEM harness capable of carrying 110W (which if I remember college is: Watts = V X Amps right...?? so 12V @ 9 or so amps ..or more likely when running, 13.5 V @ a somewhat lower amperage). If so then could I upgrade to a 20A fuse and let it go..or Do I need to rewire with a heavier gauge.??

The sets came with their own harness/relay etc..but I rather use my OEM button and set up.

The wires are small, I grant anyone that...just curious though. I would note that the 15A fuses did take some time to blow..it was like 2-3 minutes before they would. All on Headlight whether on or off made no difference .. I tried a new fuse with it on and again with another new fuse with it off...did not seem to make any difference.

so any advice would be appreciated.

Thanx,

stk

BombDocDiesel
06-07-2009, 10:57 PM
I wouldn't add a bigger fuse in there. The wiring from the factory will be the next thing to go, if you do.

Wire the relay it came with into the system. This lets you use the factory switch to apply power and switch the relay. You just need to run switched/unswitched power to the relay and then lights and run a lead from the + on the factory harness to the relay to turn-on the second set. Run the factory harness on each side to one light and set up the second light as stated. This will let you add a dedicated circuit to the second set and still use the factory switch. If the instructions have you running accessory power to the switch in the kit and then from the switch to the relay you are just eliminating the cheap switch.

steakman
06-08-2009, 12:35 PM
KEWL...Thanx Doc..!! I think I can handle that..! I have both sets of harnesses in the bag and will use one of them.!!

Big help Doc.!!

Stk

BombDocDiesel
06-08-2009, 01:33 PM
No problem. I ran them the same way. I ran my second set in parallel.

steakman
06-10-2009, 09:31 AM
yea...One thing though. What do I do with the wires for the switch...?? I am thinking that if I wire them together..it will be as if the switch is always in the "on" position. Then as the relay gets its 12V signal from the OEM Harness when the inside Fog switch is engaged, the relay powers on and bingo lights up the 2nd set ... right..??

Stk

steakman
06-10-2009, 08:27 PM
Well...did it up tonight...works like a charm.!!!

Many thanx. I know have a much better understanding of how relays work in a 12V system and will apply that to the 12V fuel pump I am about to buy..!! (still have an extra harness/relay etc.)

Thanx again BombDoc. You The Teach.!!

stk

BombDocDiesel
06-10-2009, 10:06 PM
Did it make sense running the hot from the light on the factory harness to the relay? It saves a lot of time and effort. Use what's already there.

No problem brother. People help me here all the time. Electric stuff; I know, actually went to school for that. Somehow ended up in the Army. Funny world.