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Old 11-02-2012, 07:10 PM   #66
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Originally Posted by Hybrid dude View Post
Thanks for the additional tech details.

Yes, my idea was to share the housing, although I don't think I'm that skilled and wouldn't want to create interference, neither mechanical nor electronic. Since the circuit board is the full width, I don't know if an inch of depth is enough.

Another question since you seem to have good knowledge of car electrics. Since I have a hybrid, do you think installing fog lights which bypass the BCM, just simply wired to battery, ground and switch, would negatively (npi) effect the electrical system in general? People have mixed opinions as to whether or not to mess with a hybrid system but as I see it, it does just use a regular 12v battery for regular electrics and the Lithium Ion to drive the electric motor for the drive wheels.

And to Tiger-Heli, yes the SEL model has fogs standard so the parts are available.
I don't see why it would, as long as you tap the same power source used to drive the rest of the lighting system.. I don't have alot of experience with hybrids per se.. but if the propulsion power system is separate from the standard electrical system.. you should be fine.

I would use some kind of relay system in your fog light wiring with fuse protection just for safety..

You could either use a setup like the one i used on my focus (adapted to work with the lighting system in your C-max... ) or. if you want just a simple toggle switch setup... wire it as follows...

1. Connect a wire (at least 14 gauge) from batt positive to terminal 30 of any 4 lug 40 amp general purpose relay.. (put an inline fuse in this wire somewhere rated to at least 15 AMPS)..

2. From Terminal 87 on the relay to your foglamps.. (again min 14 gauge)

3. from fog lamps to a good solid ground..

For your switch..
1. Run a 16 or 18 gauge wire from either battery positive (or preferably from an igntion switch controlled 12 volt power source or from the parking light circuit so they go off when the headlights are turned all the way off.. This way if you ever forget to turn the fogs off one day, it doesn't drain your battery) and inline put a 10 AMP fuse to your toggle switch...

2. From the toggle switch .. run to terminal 85 of your relay.. then run another 16 or 18 gauge wire from terminal 86 of the relay to a good solid ground..

This will prevent higher amp load of the foglights from having to go through the switch.. and can keep the higher load closer to the fog lights or battery in the engine compartment area..

The relay only uses a couple of amps or so to switch on and off, which keeps helps keep power going through your switch to lower safer level which will help increase switch life and less likely to cause issues in case something shorts out under the dash either during installation or if something goes wrong with the wiring down the road..
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