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12V switchable for DCC control

  • Thread starter Thread starter tim281
  • Start date Start date Feb 25, 2010

tim281

New Member
Dec 18, 2005
125
1
0
Portland, OR
Feb 25, 2010
#1
  • Feb 25, 2010
  • #1
While trying to hook up my DCC controller to the coolant overflow tank for the 12V switchable, I probed the 3 wires and found that 2 of them had +12 when I unplugged the connector to check it??
Does this mean there is a short in the ground wire? Maybe it was a bad reading because i used the chassis as a ground instead of an ECM ground?

Thanks,
T
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Feb 26, 2010
#2
  • Feb 26, 2010
  • #2
What did it show when you checked it while connected?
 

tim281

New Member
Dec 18, 2005
125
1
0
Portland, OR
Feb 26, 2010
#3
  • Feb 26, 2010
  • #3
I will try that tomorrow. Do you think it could actually make a difference if the connector was plugged in? I can't see why that would change it but I am willing to give it a shot....I am curious about it now.
 

tim281

New Member
Dec 18, 2005
125
1
0
Portland, OR
Feb 26, 2010
#4
  • Feb 26, 2010
  • #4
plugged in the connector and no change, two wires still have 12V and the other 0V.
the wire colors are:
Light Blue +12V
Black 0V
Red with Yellow Stripe +12V

The coolant overflow connector pigtail comes of the head light harness but none of the manuals or online schematics show these wires in the diagrahms. I am guess this circiut is so low priority that it is not documented. I bet the only way to really know for sure the wire designations would be to have a ford service manual.
One thing that might be a problem is that i have my intrument bezel out of the car so all the circuits for the lights are not plugged in?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Feb 26, 2010
#5
  • Feb 26, 2010
  • #5
Use the following at your own risk:

Looks to me like R/Y is the 12V feed.

LB should show ground if your sensor was dry or while the light proves-out when you turn the key on initially.

Saleen0679 can probably confirm this.
 

tim281

New Member
Dec 18, 2005
125
1
0
Portland, OR
Feb 26, 2010
#6
  • Feb 26, 2010
  • #6
Thanks Hissin. I think you are right about the R/Y wire because I did find that on one schematic that was a switchable 12V to the head lights. I figured it must be this wire also so your suggestion seems to confirm my suspesion.
I am not sure why my Light Blue is 12V yet, but I guess I am not too concerned as long as I don't have a CEL on after I get this install finished
 

Saleen0679

10 Year Member
Apr 14, 2005
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49
Yakima, WA
Feb 27, 2010
#7
  • Feb 27, 2010
  • #7
 

tim281

New Member
Dec 18, 2005
125
1
0
Portland, OR
Feb 27, 2010
#8
  • Feb 27, 2010
  • #8
Wow! Thanks Saleen0679! That is perfect. Thank you both for the great help.
 
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