Fog Lights Installation Tutorial

[DoAwEe]

Hi guys,

 

i've been looking around the internet but can not find any links on fog light tutorials for 91 corollas.

i just purchase a 91 GTi and would like to put on some aftermarket fog lights (hellas) and was wondering does anyone know or know of a tutorial link that shows you exactly how do do it ? and what you need?

 

any help is much appreciated.

[Medicine_Man]

Depends on how you want to go about it, Attached is a quick diagram I whipped up on how we do it at work. By law spotlights are required to function off high beam, So we tap into the wires on the back of the original headlight.

 

You will need some 3mm twin core cable, 4mm twin core cable, Fuse holder with fuse (25A) Depending on how big the spotlights are that might change, Switch and some crimp terminals.

 

Basically start with mounting your spotlights, Mount your relay, Wire the positive of the spotlights to your relay, Earth both the negative of the spotlights to ground, run your switch wire through your firewall, mount the switch and connect it up - when it runs past the relay cut the insulation to bare the positive and connect it to your relay, make an earth from your relay to ground, wire your switch wire to your headlight high beam, then finally connect the battery to the relay via a fuse holder...

[KE30_KE35_KE55]

also remember that if the lights are set above a certain height regardless of the brightness color they must only come on with high beam.

[DoAwEe]

also remember that if the lights are set above a certain height regardless of the brightness color they must only come on with high beam.

 

Thanks alot buddy!

 

i'll give it a go.

[towe001]

More or less the same but using less wiring. To get the power for the relay you just splice into the high beam wire at the head light (or if its for fog lights - the low beam wire). The relay won't work till you've closed the circuit at the switch.

 

To find what fuse rating you need

Voltage / watts = amps

12v / 100w = 8.33333amp (but use one thats a bit higher due to spikes when the light gets turned on, say 10amp)

Same goes with the wiring for the spot/driving/fog light. Where as the wiring for the relay/switch combo you can get away with cheap and nasty speaker wire if you feeling cheap and nasty. The relay itself only draws something around 1-2 amps when its turned on

 

But all in all keep it neat, tidy and have good clean earthing (grounding) points.

[Medicine_Man]

Thats the dodgy way of doing it sorry.. the 3mm cable should go to both sides of the headlight..

[KE30_KE35_KE55]

More or less the same but using less wiring. To get the power for the relay you just splice into the high beam wire at the head light (or if its for fog lights - the low beam wire). The relay won't work till you've closed the circuit at the switch.

 

To find what fuse rating you need

Voltage / watts = amps

12v / 100w = 8.33333amp (but use one thats a bit higher due to spikes when the light gets turned on, say 10amp)

Same goes with the wiring for the spot/driving/fog light. Where as the wiring for the relay/switch combo you can get away with cheap and nasty speaker wire if you feeling cheap and nasty. The relay itself only draws something around 1-2 amps when its turned on

 

But all in all keep it neat, tidy and have good clean earthing (grounding) points.

 

The switching circuit on this one is safer if the switching wire shorted the lights would just come on, with the top circuit if the same wire shorted the headlight fuse would blow then you could be in a lot of trouble without headlights if driving at the time.

[Medicine_Man]

You would be doing a good effort for starters to rub through Twin 3mm Gas as it is double insulated, Do you understand how the light actually functions when you switch it on and then to high beam? You aren't going to blow the headlight fuse..

[KE30_KE35_KE55]

You would be doing a good effort for starters to rub through Twin 3mm Gas as it is double insulated, Do you understand how the light actually functions when you switch it on and then to high beam? You aren't going to blow the headlight fuse..

 

its a good circuit just add a 5 amp in-line fuse i understand how the circuit works, I Have also seen how some people run wires, My corolla when i bought it had a 5mm single insulated house hold wire going from the battery terminal thru a sharp hole drilled in the firewall to the boot un fused.

[DoAwEe]

hi guys,

 

I finally got around to installing my fog lights on my 91 corolla, however I have a dilema. After following all your instructions, btw thanks to all, it still does not work. I bought a fog light wiring kit which includes the fuse and relay and this is what I did, please correct me if there are an parts which seems to be incorrect that might be the solution to my problem.

 

 

1. i mounted the relay and fuse in my engine bay and connected the fog lights. The relay has both the power and earth cables for the fog lights running directly from the relay.

 

2. i connected relay earth cable to battery (negative).

 

3. i connected relay power cable connected via fuse to battery (positive).

 

4. i then tried connecting the extra wire both to my normal head lights and high beam just to test to see if it is working. and just my luck, nothing works.

 

HOWEVER, i can hear the relay working when i press the on/off switch, meaning there is power going into the relay but still nothing from the fog lights.

 

i checked to see if the fog light bulb is busted, but all looks fine. I wanted to make sure by testing it out.

i connected the fog lights directly to the battery, positive cable to positive terminal, negative cable to negative terminal, still nothing.

 

is this an effective method of testing the light to see if it works?.

 

anyways, i am all out of ideas atm, if anyone out there has any suggestions, please no matter how silly or strange, i am willing to give it a go, i am that desperate to get it up and running.

 

Thankyou in advance for your help and time reading this thread.

 

best regards.

 

D

[Medicine_Man]

1. i mounted the relay and fuse in my engine bay and connected the fog lights. The relay has both the power and earth cables for the fog lights running directly from the relay.

 

The relay only feeds power to the fog lights, it doesn't feed the earth, the earth goes to the body/frame of your car or your earth side of your battery..

[DoAwEe]

The relay only feeds power to the fog lights, it doesn't feed the earth, the earth goes to the body/frame of your car or your earth side of your battery..

 

but there are main cables running from the relay which i am pretty sure ar for the fog lights and every cable has 2 mini cables which are for each fog light. power and earth.

 

how can i earth the fog lights when they are already connected to the relay?

 

regards,

 

D

[Medicine_Man]

Without looking at it, It makes it hard to say. No headlight relay setup I know of earths the lights through the relay..

[DoAwEe]

unless they are both power cables? for 4 lights? thats all i can think of.

[DoAwEe]

i just tried grounding the lights separately as well still nothing.

 

and i can confirm that the ground cables from the fog lights which goes back to the relay does work.