bpr0422

Since so many people are asking, "What fog lights should I get?".

I'm sick and tired of answering the same general questions of which is better, OEM or after-market. Also the "Help my _Brand_ fogs don't work." Thread pops up way to often. Some are okay, like the one with the melted harnesses, but others are just -bleh. Also everyone's answer in those are "Check your grounds/connections" or "_Blank_ sucks! go get OEM!" - what BS

This is NOT a How to Install the fogs in your car that is here: https://honda-tech.com/zerothread?id=1352749

If your wondering about EKs or another model, they are all installed the same way
Remove Bumper -> Cut/Pop out openings -> Route wires -> connect wires -> Test -> Put bumper back on

This is all IMO of course, but I do have some facts on wires to back me up.

Below is a Testing procedure...
If your fogs do not turn on: You will need a multimeter.
1. Check Fuses - Fog Light Fuse and Dash Light Fuse
Blown - Replace - start again at step 1
Good - step 2

2. Check Grounds: Check for continuity between the ground at the fogs (black wire), and the ground ring. Then check your INTERIOR ground, best place is between relay harness (pin attached to black wire) and interior grounding terminal.
Good continuity - step 3
bad - replace wires, exterior/interior harness - start again at step 1

3. Check Voltage at Fogs - Do you get voltage at the fogs?
Yes - Inspect Bulbs and their connections, test for continuity between pins outside of housing, and corresponding connections inside
No? Step 4

4. Check Voltage at Harness Joining Point
Yes - Bad Exterior Harness - Begin testing at step 1.
No - Step 5

5. Test Relay - Provide Power and Ground to Relay's coil, test for continuity between the two Common and N/O pins. If no continuity with powered coil, bad relay - replace, restart testing at step 1. If relay is good, and still nothing go to step 6.

6. Test for Voltage at relay harness' coil pin.
No - Step 7b
Yes - step 7a

7a. Check for continuity between grounding point and ground pin at relay harness

7. Test for Voltage at relay harness' power pin
No - Step 8
Yes - Something is f*ed up - new harness or rewire harness.

8. Check continuity on the fused wire.
No - replace fuse wire with one from radio shack
Yes - Step 9

9. Test for continuity between each pin in green plug to corresponding terminal.
* Black wire - Interior ground
* Yellow - Relay Coil Pin
* Red - Dash Light Input wire
No - Bad interior harness - replace begin testing at step 1
Yes - Bad Dash switch - replace begin testing at step 1

That was the test procedure starting from the outside in.

Now to the main post!

=============================================

Halogen Fog Light Bulbs – Watts, Amps and Voltage

The regular fogs use 12v 55w Bulbs this is a draw of ~4.6amps (55w/12v=4.58333amps)

Since both fogs are on the same circuit the total load is actually 110w. This translates to a draw of ~9 amps.

However, brighter after-market bulbs are usually 12v 100w bulbs this is a draw of ~8amps (100w/12v=8.333amps)

Since both fogs are on the same circuit the total load is actually 200w a total of ~17amps!

The fuse in the after-market fog-lights is rated at 15amps!

A draw of 17amps should blow the fuse, however the load is actually less than 17amps due to resistance in the wiring and variance in voltage which explains why the fuse does not blow.


AWG – Wire Size and Fuses Dictates the Max Amp Load

17amps is too big of a draw for 18ga wiring, it must be upgraded to something thicker, and since wires are only easily found in 2ga stepping 16ga is the cheapest step up.

The 16ga is normally rated at 22amps, 14ga at 28amps,12ga at 44amps and 10ga at 55amps. All this information can be found from this website: http://www.powerstream.com/Wire_Size.htm

* Yes there are other factors that determine max amps on a wire - but to make things simpler: larger gauge more amps. *

ESSUE/DEPO/RAYBRIG/PASSWORD:JDM SUCKS!!!! REAL OEM/JDM PWNS!!!!!

That is entirely incorrect. The Honda OEM is wired up EXACTLY the same way as these aftermarket ones are; one wire providing 12v to 2 fog lights. Maybe Honda uses a different wire gauge; however I highly doubt it because these aftermarket fogs are based on the OEM fogs.

WELL HONDA USES BETTER WIRES!!!
- Password:JDM is a pretty big site, and they have a lot of customers. If the after-market wiring is so bad they would be getting a lot of complaints, but it seems to me that they are still up and running. So there must be nothing wrong with the harness. All of the brands use the same wiring, there really isn’t much difference between them; because they are all rated at 15amps. – Only reason why Password:JDM sells it at a higher price is because of the services they provide, and their claim to OEM quality. Don’t get me wrong, if I had the money to buy from them I would and if they are still around within 5 years, I will buy from them – because some things they have you just can’t find anywhere else.

HONDA MAKES A BETTER LOOKING SWITCH!
- You got me there; colors are hard to match without knowing the exact recipe. However, it’s just a EXPLETIVE switch!!!! The real part that matters is the wiring.

So if Honda uses 18ga wiring, and rates the circuit at 15amps what makes it so much better than the OEM Look-a-likes? Nothing.

- I do not know what amp rating Honda uses for their fog light fuse. I’m just guessing – If you give me what amp rating Honda uses for their fog light fuse, I’ll fix my post accordingly.
- Wiring assumption based on OEM EK fog Wiring (1-Pin connector to provide power): http://www.handa-accessories.c...s.pdf


What about my After-Market Headlamps?

So then why is it okay to use higher voltage bulbs on your h4 headlights?
The way that the headlights are wired up, is each side is on its own individual circuit.

Look at your fuse box under the dash! Each left/right low/high has its own fuse, which means it has its own circuit. The fuse states the circuit's max load.

Each circuit has a max load of 10amps (check your fuse box).

OEM H4 is 12v 55w/60w High/Low respectively. Amp draw is ~4.6amp/5amp respectively.

High Output After-Market H4 is 12v 90w/100w. Amp draw is 7.5amp/~8amp respectively.

These amps are within the limits of Stock wiring.

================================================== ===

IMO: Replacing your stock headlights with higher watt bulbs is a bad thing; it can lead to damaged harnesses. The only alternative to that is buying better quality/higher output bulbs that are rated at the same wattage that your stock ones are.

Please take a note that I am using 12vdc as the normal voltage, however in real life that voltage shall vary from 10.5v to 14.5v - so the amp load can increase or decrease depending on the output.

All info on wires/amps can be found here at http://www.powerstream.com/Wire_Size.htm and http://www.powerstream.com/Amps-Watts.htm

================================================== =
Below is the Generic wiring diagram for fog lights in Hondas.
The pictured fuse box is from an EG (92-95 Civic)



Modified by bpr0422 at 11:48 PM 11/15/2006

nighttrain33

Good info Let's keep this up since I see foglight questions 20x per day.

-Shane

RHDSirEG6

thanx for the useful tech info

BlueIntegraBoy

iTrader: (5)

Very nice diagram. Will help a lot of people.

bpr0422

Any comments, thoughts? counter points?

aka bump b4 i sleep.

Jimmy

iTrader: (5)

Pm a moderator and get [faq] added to the top of this thread and post it in the faq.. otherwise it isn't going to go anywhere

HondaJack

Great info man! Well done! Really wish I had that when I was trying to get my fogs to work.

attentionwhore

Excellent write-up. This should help out many a person and definately to the stickie request

yee SERIOUS

iTrader: (1)

good stuff. should be added to FAQ

qat727

Great info and a nice diagram. Thanks!

DFW

iTrader: (1)

Man these fogs just keep giving me problems...

Had them on and working fine for couple days, then passenger side only turns on when it feels like it I guess, then just stops working. Bulbs were good, couldn't find a short, grounds were good, both sides had 12v....Driver side worked fine btw.

Now I took the whole set up out and it's been about a month. Just installed them again, now the driver side is out and the passenger side works!

jdmsiR20

damn, that diagram is killer

SovXietday

I have a set of OEM ones, directly from Honda.

OEM = Raybrig

The OEM ones run into an already existing harness which makes installation a bit easier, and they also turn off when you switch to highbeams (which is the law btw).

I don't have experience with the aftermarket ones, but figured I'd throw the info out there anyway. Good thread, good writeup.

tmramsburg

I have a 00 civic.For the inside harness I dont know where to plug 2 of 3 brown connectors. The one goes behind the fuse/relay panel. I have a helms, so i can get familarized with locations. These are the ebay fogs.

italian_virus

bump for old times sakee!


one question i have to ask is.. the red wire coming from your switch into your fuse box.. that is going into slot 4 in your fuse box? & what if you already have something connected into that slot ( i believe its either my autostarter or car alarm).. can i use another slot? or does it have to be that specific one?

thanks boys for any help!

93egSLEEPER

Are you wiring them for a switch that you have manual control over OR are you looking to tie them in with the corners/headlights?

If your going to use a manual switch run it top an ignition switch powered source and run a 15-20amp fuse on it for protection.

deschlong

iTrader: (8)

I should add this link to the FAQ, in case anyone's unhappy with the quality of their switch and want to replace it with an OEM JDM one, but have it function like an OEM CDM/USDM one should.

LINK: [FAQ] DIY: Convert JDM OEM 92-95 Civic Foglight Harness to OEM CDM/USDM Legal Spec

italian_virus

its an after-market switch came with the fog lights.

italian_virus

anyy idea anyonee?

MikeANZ

Great write-up. FTR, and to answer an old question, I have two OEM foglight harnesses and both have 15A fuses fitted.