Front Fog Lamps - Wiring info

[fanx_ta_ra]

Hi All

Am going to fit an extra pair of fog lamps into the openings either side of the front number plate. The fitting is no problem but what I need to know is am I able to tap into the positive and negative feeds that are supplying the factory fitted fog lights so as they all switch on together or will this overload the switch. The rear bumper mounted fog light, although on a different switch, is taking its supply from the front fogs as well.

Kind Regards, Andy

[g8dhe]

The factory fitted Fogs have there own relay;

When you switch a total of 110W on from cold you will draw a surge current getting quite close to 15Amps. What extra wattage will you be adding with the additional lamps ?

[fanx_ta_ra]

Hi Geoff

Thanks for your response. The new lights have 55W halogen bulbs and the instructions say that if I use a switch rated at under 10amps then I need to run the wiring through a relay. The existing switch does have a relay plugged into the back.

Really wanted them to switch them on and off from the same switch but if this is not possible then where would be the most practical place to pick up the 12V DC feed bearing in mind I only want to be able to use them in conjunction with the main headlights. The switch I would intend to use for this is a genuine Mazda fog lamp switch as per the original ........ any ideas on the rating of this switch?

Many Thanks, Andy

[dave_aber]

Do you mean that you want them as fog lights with the dipped headlights, or as spotlights / driving lights with the main beams?



I have the original fogs fitted, which this Bongo never had originally, using my own additional relay and a Mazda front fog switch. They come on with the sidelights, as long as the fog switch is latched in. The spotlights are wired to operate along with the main beam, again wired through an additional relay, and a Mazda spotlight switch (from a 323, which fits in perfectly)

I have replicated the wiring as shown by Geoff for the fogs - picking up the main power from the fusebox under the bonnet, and fed the trigger line from the sidelight circuit.

For the spots, I did the same, but the trigger line is fed from the high beam circuit, via the switch.

[fanx_ta_ra]

Hi Dave

Thanks for the response. I want them as fog lights with the dipped headlights as per the existing fog lights. I think I may need to replicate the wiring as per Geoffs diagram because as I understand it if I try to run all four lights that are 55W each totalling 220W on a 12V supply this equates to almost 19 amps and that maybe too much for the switch/relay ....... what do you think?

Regards, Andy

[g8dhe]

Its not the rating of the switch that is in question, the switch only controls the relay at a few 10'smA, its the relay contacts and the power feed to the relay contacts & lights that needs to be rated at or above 15 Amps, most relays are rated at least 20Amps so that shouldn't be a problem. Picking up a power feed is probably easiest from the back of the X02 fuse box in the centre under the bonnet;

The one circled in white appears to be spare in the wiring manuals.

[dave_aber]

IIRC, that's where the factory fit fogs get their power - I tapped into the 'correct' fuse location

[fanx_ta_ra]

Geoff, thanks for all your help. Your info has been priceless and has helped me out no end!. Please don't tell me you went out in the freezing cold to take that photo just to answer my query!!

Regards, Andy

[g8dhe]

No chance of wandering out at this time and temperature! I have a good stock of pictures of the get-at-able parts used for the on-line wiring manuals !
The normal fuse for the Front Fogs is this one;


If you make changes as outlined below, then do make sure ALL batteries are disconnected before starting any work!
If you don't have ABS on your vehicle then the Yellow fuse 3rd from top position could be used as its already wired to the 100Amp feed, change the fuse to 15 Amp and you would need to get the fuse box out (not sure its that easy) and isolate the wire going to the ABS (Orange/Blue) and replace it with the wiring to your relay contacts.


If you do that then can I also suggest that you ALWAYS leave a note with the vehicle as to changes that you have done perhaps in the vehicle manual, and even a small note tucked into the fuse box itself saying where to look for what has been changed! I suggest this as another thread running at the moment where changes have been made and no clues as to what wiring has been altered is causing some grief for the owner!

[fanx_ta_ra]

Thank goodness for that Geoff. And good idea about leaving a note with regards to any alterations .... was just reading the post regarding the poor guys wiring. Can I ask you one final question for future reference. With regards to relays am I correct in assuming that I could tap into, lets say a 30A relay, as long as the total load does not exceed 30A. This may sound simplistic, but hey thats me!!

Thanks for your time and help, Andy

[g8dhe]

No you can't tap into an existing relay as such - the relay is a magnetically operated switch, the dashboard switches if they can't handle the current needed simply operate the relay which has much larger contacts to handle the current - so you have a separate relay for each function.

[fanx_ta_ra]

Geoff, thanks again ........ I get it now and the lesson endeth here .

Just been looking at your website. Very impressive indeed and some of those locations bring back some happy memories for me and others have given me itchy feet for next year.

Kind Regards, Andy