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Electrical Mystery electrical dash connectors

  • Thread starter Thread starter plout99
  • Start date Start date Sep 6, 2021
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plout99

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Sep 4, 2021
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Sep 6, 2021
#1
  • Sep 6, 2021
  • #1
So I have reinstalled the dash in the 89 gt my son got from his great uncle and have two connectors left I can’t find a mate for. I think the wide flat connector is for the cruise control maybe it passes

thru the firewall to the left of the vacuum line for the cruise. The 4 wire plug I have no idea.
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
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#2
  • Sep 6, 2021
  • #2
The bottom plug looks like clutch safety switch but I'm sure someone with a schematic will come in and verify/correct that. There no plugs on these cars that remain a mystery so hang in there.
 
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plout99

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Sep 7, 2021
#3
  • Sep 7, 2021
  • #3
Thanks for the suggestion I have both clutch connectors hooked up. I did figure out the wide flat plug is part of the cruise control after doing some eBay searchin. The car is missing the cruise control part in the left fender well. Just need to figure out the 4 plug
 

Wayne Waldrep

Before I post a pic, do you have one of yours?
20+ Year Stangneter
Apr 14, 2003
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659
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Sep 7, 2021
#4
  • Sep 7, 2021
  • #4
Pm me your email and I'll send you the 1988 EVTM pdf. It won't let me attach it now for some reason.
 

KRUISR

10 Year Member
Apr 16, 2015
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#5
  • Sep 7, 2021
  • #5
In looking at the wiring diagrams in my Chiltons manual, the large flat connector (8 pins is what I count) is possibly the A/C Fan Controller that is listed as a 4 cylinder only controller - therefore you would have nothing to connect to. The 4 pin, could be the feed to the Rear Window Defroster or Convertible Top functions (again possibly not features on your car).

Just my thoughts.
 
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plout99

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Sep 8, 2021
#6
  • Sep 8, 2021
  • #6
Did Ford include all the available connectors in the wiring harness even if the car didn't have that option? Thanks for the schematic offer Wayne, I have the 89 evtm so if Ford did put all the available option plugs in the harness then the 4 pin is the rear window defrost like Kruisir suggested since this car isn’t a convertible and was bought in south Florida by my sons great uncle and doesn’t have rear window defrost. I hadn’t looked at the rear defrost or convertible schematic since it didn’t have those options.
 

Mustang5L5

That is…until I whipped out my Bissell
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Sep 8, 2021
#7
  • Sep 8, 2021
  • #7
plout99 said:
Did Ford include all the available connectors in the wiring harness even if the car didn't have that option? Thanks for the schematic offer Wayne, I have the 89 evtm so if Ford did put all the available option plugs in the harness then the 4 pin is the rear window defrost like Kruisir suggested since this car isn’t a convertible and was bought in south Florida by my sons great uncle and doesn’t have rear window defrost. I hadn’t looked at the rear defrost or convertible schematic since it didn’t have those options.
Click to expand...


Yes

What are the wire colors?

I'll be honest, the pictures aren't the best. The top plug is either the cruise control amplifier, or the 4cyl fan controller. The 4 cyl fan controller plus is yellow, while the cruise is gray. IF the car actually has cruise control there will be a 2nd plug from the servo in the fender plugged into the amplifier. If the car doesn't have cruise, that single plug hangs loose.

Bottom plug i'll need wire colors for.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,235
17,920
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Massachusetts
Sep 8, 2021
#8
  • Sep 8, 2021
  • #8
You said you have an '89 EVTM right?

Page 108. Verify the wire colors for the connector labeled "C220" into the solid state amplifier. See if the colors match up to what is listed here


Bottom plug is not for the defrost relay. That plug looks different. I think this plug is for the horn/cruise. It's a 4-wire plug, but two separare 2-wire plugs connect here. One for the horn, and the other for the cruise control switches from the steering wheel.

If you don't have cruise, only one of the 2-wire plugs connects here and the other large plug hangs loose
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,235
17,920
224
Massachusetts
Sep 8, 2021
#9
  • Sep 8, 2021
  • #9
Here’s the plug on my ‘88. You can see two different plugs connect to it.

I reloomed my dash harness, so this plug might not be in the same exact spot as it is on your car.

 
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plout99

Member
Sep 4, 2021
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Sep 8, 2021
#10
  • Sep 8, 2021
  • #10
Mustang5L5 said:
Yes

What are the wire colors?

I'll be honest, the pictures aren't the best. The top plug is either the cruise control amplifier, or the 4cyl fan controller. The 4 cyl fan controller plus is yellow, while the cruise is gray. IF the car actually has cruise control there will be a 2nd plug from the servo in the fender plugged into the amplifier. If the car doesn't have cruise, that single plug hangs loose.
Click to expand...

The missing part for me was that Ford included all the connectors for all options in the dash harness. I went back to my 89 evtm and the 4 wire plug is for rear defrost or convertible top. Since the car has neither I didn’t look at them to match wire colors.
 
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plout99

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Sep 4, 2021
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Ohio
Sep 8, 2021
#11
  • Sep 8, 2021
  • #11
Thanks for the help everyone as of tonight the car will crank over, lights,blower,windows all function. The car has cruise but the previous owner removed the servo in the fender well so it might not ever get replaced. I haven’t tried to start it yet since I want to remove the old fuel and change filters and fluids before it’s started and since it has the infamous bbk fuel rails I want to make sure my fire extinguishers are full or that my homeowners insurance is up to date.
 
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