Wiring Help

[Soup5915]

Hello all. I’m new to the forum and I have searched everywhere for this info but can’t find anything so I figured I’d ask the pros. I purchased an 87 GT Vert a little over a month ago and working on getting it on the road for the spring. The car sat for three years and ALL the weather stripping is shot and the interior needs a refresh. I took the dash out , and the previous owner shredded the wiring, looks like spaghetti. I took out the remainder of an alarm system and parts of a sound system, but I have these 4 connectors that I do not know what they are. The two bigger plugs are under the drivers side, left of the steering column, I believe the yellow one is something for the 4cyl LX. The other two are just to the left of the heater box. Any help is greatly appreciated. Thanks.

 

[Mustang5L5]

Big yellow one is 4cyl fan relay. Just ignore that. Other one connects to cruise control box in the background.


For the smaller two plugs. The one with the red/green stripe wires connects to the clutch switch on the quadrant side of the pedal box. It’s to disengage the cruise. Needs to be connected or have a jumper installed.

Other one escapes me at the moment. Too many beers

 

[Soup5915]

Big yellow one is 4cyl fan relay. Just ignore that. Other one connects to cruise control box in the background.


For the smaller two plugs. The one with the red/green stripe wires connects to the clutch switch on the quadrant side of the pedal box. It’s to disengage the cruise. Needs to be connected or have a jumper installed.

Other one escapes me at the moment. Too many beers

Thank you. I ignored the yellow connector and plugged in the grey connector to the cruise control. As for the red/green wire connector I don’t see were this goes. I see a switch attached to the clutch but there are two plugs already there also this cable would not reach over there from where it comes out of the main harness bundle. And still no idea on the other plug.

 

[Soup5915]

Thank you. I ignored the yellow connector and plugged in the grey connector to the cruise control. As for the red/green wire connector I don’t see were this goes. I see a switch attached to the clutch but there are two plugs already there also this cable would not reach over there from where it comes out of the main harness bundle. And still no idea on the other plug.

Ok. I found the connection to the red/green wire connector. One more to go!!!

 

[manicmechanic007]

I agree with the above posts
There are plugs that do not go to anything unless you have the option for it
Fog lights for example
Same with air bags
The wiring was there before the bags were
Hence the Aerostar Lawsuit in '86 or?

 

[Mustang5L5]

What are the wire colors on the final plug? I can check my EVTM in a bit. I think I know what it is but want to confirm first

 

[Soup5915]

What are the wire colors on the final plug? I can check my EVTM in a bit. I think I know what it is but want to confirm first

In looking at the three wires its — blue/yellow — black/white — black/white

 

[Mustang5L5]

Looked on my ‘88. That particular connector is not plugged in. However, my car is a hatchback. Unsure of that plug would be connected on a vert or 4cyl.

I can check my diagrams later

 

[Soup5915]

Looked on my ‘88. That particular connector is not plugged in. However, my car is a hatchback. Unsure of that plug would be connected on a vert or 4cyl.

I can check my diagrams later

Thanks, I really appreciate the information. If you don’t mind I did find another plug that has no home. It comes out of the main harness with the left side cluster plug as well as the flasher relay and dimmer switch. It’s odd shaped plug with 5 wires.

 

[manicmechanic007]

Looks like a rear window defroster latching relay connector
Could be any other old style relay like a horn relay
The pigtail is taped tight to the harness so I think the car did not have that particular option
Some plugs the factory uses to fire systems up
It could be one of those

 

[Mustang5L5]

That is the plug for the rear window defrost relay.

Since you have a convertible, it’s not used and should be empty.

 

[Soup5915]

That is the plug for the rear window defrost relay.

Since you have a convertible, it’s not used and should be empty.

Thank you so much for all the info. Now that all the extra wires have been removed and all the plugs are accounted for its time to check all connections to make sure that all accessories/lights are working. Thanks again.

 

[Dan02gt]

In looking at the three wires its — blue/yellow — black/white — black/white

I think that is the plug connects to the clutch switch for the neutral sensing system. The neutral sensing system tells the computer when the car is in gear or not and if the clutch is pressed in or not. This is so the computer can try to prevent stalling.

 

[Mustang5L5]

Dan,

That plug is on the left hand side of the pedal box. This one is on the right side. I’m also familiar with the plug you speak of and it looks different than this