WIRING MODS

[marshtex2]

WIRING MODS ON THE WHITE HORNET (the name I gave to my platinum white C-Max SE)

 

For reader convenience, I've split my original starting post, first getting quickly to looking at the finished project then getting into the details of doing it.

 

Realize that in modifying wiring on the C-Max we should not tap into its in-place wiring system.  That is a multiplex system and is destroyed if we cut into it like we may be used to doing in old conventional wiring systems.  However, for example if you want a device to be powered when backing up (e.g., a back-up camera) it is safe to go to a backup light bulb and right there tap into its wire but you cannot get that power at the shift stick reverse position in a multiplexed system.  So I wanted to get 12V from a fuse and wire it to my application the old fashioned way.

 

Objectives:

1. Daytime running lights (DRL).  These should automatically turn off when ignition is turned off.  In addition I wanted to be able to switch them completely off.  Light electrical load.

2. Alarm horn.  This would need a little button switch.  Power could come from always on or switched on by ignition.  Very brief electrical load.

3. Always on outlet for Garmin 2720 GPS.  Light electrical load.

 

So I would need two power sources, always on and switched on by ignition.

 

Look at my finished product.  Fortunately the headlight switch module is easily pried out of the dash panel with a thin flat-blade screw driver that reveals a place where the special wires can be managed.  So first, the DRLs.  See the first two jpgs.

 

Then the set up at the headlight switch.  DRL switch on the right, little red horn button on the left.  See the third jpg;

 

Then the outlet for the GPS and a manual switch for it, the larger red button, fourth jpg.

 

I plugged the Scangauge into the lower OBD II outlet and ran its wire through the other OBD area and through a notch made in its panel.  Then see the finished set up, jpgs 5 & 6.

Edited February 3, 2014 by marshtex2

[marshtex2]

WIRING MODS ON THE WHITE HORNET (the name I gave to my platinum white C-Max SE)

 

For reader convenience, I've split my original starting post, first getting quickly to looking at the finished project then getting into the details of doing it.

 

Now for details.

 

I found that all the fuses in the box under the glove box are always hot, not good for DRL.  Checking the fuse box in the engine compartment, I found always on, simply switched on and switched on ones that also come on when a door is opened.

 

OK, that will require running wires through the firewall to get from fuses to switches near the driver.   I did that by using the grommeted hole through which the hood-opening cable runs.  Using a length of welding rod or larger plain copper house wire, I poked around that grommet where the cable goes in, above the driver's left foot.  After a bit of a struggle I got it through and slid it to where I could grasp it from the engine compartment side. 

 

Thinking of the DRL system, I needed a switched 12V source, get it inside and through a manual switch, and then back out to the DRL LED strip I was going to use.  So I fastened two small-gauge wires to the end of my pull through wire which I pulled back through the grommet bringing my hook-up wires along.  The grommet is very tight and will easily pull taped wires off the pull wire so that part has to be meticulously done.  The most certain way is to use a copper pull wire and solder the lead wires to the end of it.

 

Also needed are an always hot wire, and another wire to get out to the alarm horn which I mounted in the back of the engine compartment.  One by one I taped a new wire onto a midpoint of a little wire just pulled through and pulled it through.  While at it I pulled a fifth wire through for possible later use.  Whew!

 

Let's look at the fuse box and the fuse identifications in the owner's manual, pages 267 & 268.  Down the left side as we look at it, always hot are F 20, 21, 24, 30 and a blank position at 31.  In the center are F 23, 26 and 27 which are hot only when the ignition is turned on.  Again, as we look at it, the hot side of each fuse is on the right.  I positioned my little wire alongside the left fuse prong and shoved the fuse in its slot thereby allowing fuse protection for my application.  Using F26 for my switched needs the little green wire is seen in the photo.  For always hot you see the little black wire going into F31 where I put a fuse with the little wire wrapped around its left prong.  I filed a notch alongside the big wire harness entry grommet to run the little wires into the fuse box.  Along the front edge F 32, 33, 34, 35 and 36 are unpowered unless the ignition switch is turned on or a door is opened.  I did not use any of these.  There you have it.  See the jpg.

Edited February 3, 2014 by marshtex2

[Smangerer]

I ran my LED strips to the rear wiper fuse which is always on with ignition. I tossed in a FOB switch in line so I can power them off if needed. 

 

I apologies if this is redundant.