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66 Mustang - need to find a 12v source

  • Thread starter Thread starter stangman16
  • Start date Start date Sep 24, 2009

stangman16

Active Member
Nov 16, 2004
640
4
29
San Antonio, TX
Sep 24, 2009
#1
  • Sep 24, 2009
  • #1
Hi,

Changing out the EFI harness in my car with the Ford Racing harness and it says to connect to a 12v crank only source. I've done a search for a bit and the only thing I can find is putting it on the "I" on the starter relay (which is a '92 model w/the built in resister or diode..can't remember what it was).

Where can I find a crank only 12v source?
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Sep 24, 2009
#2
  • Sep 24, 2009
  • #2
stangman16 said:
Hi,

Changing out the EFI harness in my car with the Ford Racing harness and it says to connect to a 12v crank only source. I've done a search for a bit and the only thing I can find is putting it on the "I" on the starter relay (which is a '92 model w/the built in resister or diode..can't remember what it was).

Where can I find a crank only 12v source?
Click to expand...

The S terminal would be a better source. The I terminal gets partial voltage feedback when the ignition is "ON". The S only has power when the key is in the "START" position.
 

stangman16

Active Member
Nov 16, 2004
640
4
29
San Antonio, TX
Sep 24, 2009
#3
  • Sep 24, 2009
  • #3
2+2GT said:
The S terminal would be a better source. The I terminal gets partial voltage feedback when the ignition is "ON". The S only has power when the key is in the "START" position.
Click to expand...

Sounds good - thank you!
 
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