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Electrical Question

  • Thread starter Thread starter parrish5o
  • Start date Start date Feb 24, 2009

parrish5o

New Member
Dec 22, 2008
2
0
0
Dirty South
Feb 24, 2009
#1
  • Feb 24, 2009
  • #1
Got in my car this morning and as usual the windshield is fogged up. I turn the defrost on and click the fan to max and nothing happens. As the engine heats up I feel heat coming from the vents, just no fan. In my former job I had an F250 company truck, there were six of them from a 2000-2008 between us. In almost six years of me working there I saw this happen to five of them including my 07 when it was less than a year old. In every one it turned out to be simply replacing the switch. I hope that is all that is wrong with mine but I'm not sure how to troubleshoot this. Since the 250 was a company truck all I did was drop it off at the Ford dealership and all I was told when I picked it up was "we replaced the switch". If possible I would rather fix this myself because I have to pay for it this time.
 

Saleen0679

10 Year Member
Apr 14, 2005
876
24
49
Yakima, WA
Feb 24, 2009
#2
  • Feb 24, 2009
  • #2
Replace a 1979-1993 Ignition Switch Assembly
 

parrish5o

New Member
Dec 22, 2008
2
0
0
Dirty South
Feb 24, 2009
#3
  • Feb 24, 2009
  • #3
Never would have imagined that the ignition switch may be the culprit.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
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Dublin GA
Feb 24, 2009
#4
  • Feb 24, 2009
  • #4
Check the #9 fuse first...
Diagram courtesy of Tmoss & Stang&2birds


Heater circuit wiring for 93 Mustang, years 87-92 will be similar...


Then check to see that one of the vacuum lines that control the heater didn't break...




See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Mustang FAQ - Engine Information Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for94-95 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif
 

parrish5o

New Member
Dec 22, 2008
2
0
0
Dirty South
Feb 24, 2009
#5
  • Feb 24, 2009
  • #5
Thanks jrincher, you are the one I thought of first thing this morning when I realized it didn't work. You are no doubt a wealth of knowledge
 
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