Technical Fog lights instalment

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Technical Fog lights instalment

smandanda

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Ive got all abarth trim for my standard cento. Is there any way i can connect fogs to car that originally came without ones? Any advices?
 
Do you mean you want to install the lamps and rig them up to a standard switch/system?

There *may* be existing wiring already behind the switch panel.. in which case you would only need to fit a factory switch (even a second-hand rear fogs switch would do), connect it to the factory wiring/connector block and then everything inside the car would work: the fogs would only come on with the lights, and you might even get the front fog-lamp switch illuminated on the dashboard.

You would only have to find (or fit) a relay and wiring to feed the lamps.


If you have no wiring already present, then you need to rig the lights up slightly more tricksy.

First connect a wire to the power wire feeding the sidelight (you'll need to piggy-back or splice it in). This lead is "live" when the sidelight is on.

Connect the wire to a relay inside the engine bay and run another wire from the opposite relay pin to your switch inside the cabin. The other pin on the switch will have a lead to earth.

If you want/use an illuminated switch (ideally, since the dashboard tell-take light won't work this way) then that will need a separate power feed from the fuse box, but will earth through the earth wire. Easiest thing is to use a piggy-back power line (fused 5A) from the same fuse that protects the headlamps.. but use the headlamps fuse in the "headlamps" position and the 5A fuse in the "piggyback" slot.

Back to the relay... that needs a power feed from the battery. You can run a wire directly from the + terminal to the relay but fit a 20A fuse in-line.

The opposite pin goes to the lamps (again, you will need to splice the wire into two) and each lamp should be earthed separately.

This way, turning the sidelights on will arm the relay circuit, so the lamps can only work when the lights are on.. in case this a local regulation/requirement. They will be controlled by the switch in the cabin. The sidelights wiring will be able to cope with the extra load of running the relay.

If nobody cares where you are that the foglamps come on with the lights, you can wire the relay in series with the switch (the pin that was "earth" above). This circuit is earthed by the relay exit pin being connected to an earth. This will let the lamps come on regardless of the car lights, so is likely not a "legal" setup.


Anyhow, that's how I'd do it... so apologies in advance if your car catches fire using this method, or if some auto electrician thinks it's dumb "because..." (in which case they'll tell you how to do it properly.. :D



Ralf S.
 
Do you mean you want to install the lamps and rig them up to a standard switch/system?

There *may* be existing wiring already behind the switch panel.. in which case you would only need to fit a factory switch (even a second-hand rear fogs switch would do), connect it to the factory wiring/connector block and then everything inside the car would work: the fogs would only come on with the lights, and you might even get the front fog-lamp switch illuminated on the dashboard.

You would only have to find (or fit) a relay and wiring to feed the lamps.


If you have no wiring already present, then you need to rig the lights up slightly more tricksy.

First connect a wire to the power wire feeding the sidelight (you'll need to piggy-back or splice it in). This lead is "live" when the sidelight is on.

Connect the wire to a relay inside the engine bay and run another wire from the opposite relay pin to your switch inside the cabin. The other pin on the switch will have a lead to earth.

If you want/use an illuminated switch (ideally, since the dashboard tell-take light won't work this way) then that will need a separate power feed from the fuse box, but will earth through the earth wire. Easiest thing is to use a piggy-back power line (fused 5A) from the same fuse that protects the headlamps.. but use the headlamps fuse in the "headlamps" position and the 5A fuse in the "piggyback" slot.

Back to the relay... that needs a power feed from the battery. You can run a wire directly from the + terminal to the relay but fit a 20A fuse in-line.

The opposite pin goes to the lamps (again, you will need to splice the wire into two) and each lamp should be earthed separately.

This way, turning the sidelights on will arm the relay circuit, so the lamps can only work when the lights are on.. in case this a local regulation/requirement. They will be controlled by the switch in the cabin. The sidelights wiring will be able to cope with the extra load of running the relay.

If nobody cares where you are that the foglamps come on with the lights, you can wire the relay in series with the switch (the pin that was "earth" above). This circuit is earthed by the relay exit pin being connected to an earth. This will let the lamps come on regardless of the car lights, so is likely not a "legal" setup.


Anyhow, that's how I'd do it... so apologies in advance if your car catches fire using this method, or if some auto electrician thinks it's dumb "because..." (in which case they'll tell you how to do it properly.. :D



Ralf S.

Thank you sir :)
 
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