Relays Under the Dash

[HB Chris]

I have been trying to help Roger in New York sort out his wiring as he reassembles two coupes. The wiring diagrams are hard to read sometimes and if you have a 73 1/2 when window motors/switches/circuit breakers were added you have to use the early diagram as well as the 74 diagram.

There are six relays under the dash starting with the 73 1/2 models: Wipe/Wash #1, Load Shed #2, Window Load Shed #3, Window Load Shed #4, Changeover (for heater fan with A/C) #5 and the Hazard/Turn Relay #6. See the photos below:

 

[HB Chris]

Wire colors for my 73 1/2 did not always match the pre 73 1/2 diagrams or the 74 diagrams which I found strange.


Relay 1 – Wipers thru 73 (these match)
Green/Black (2)
Brown/Red
Black/Violet
Black/Blue
Black/Red
Brown (2)
Brown/Black (2)

Relay 2 – Load Shed thru 73 (these match)
Red (2)
Green
Brown
Green/Red


Relay 3 – Window Load Shed 73 ½ (did not match 74)
Green/Red (2)
Red
Brown/Red
Red (2)

Relay 4 – Window Load Shed 73 ½ (did not match 74)
Red
Brown (2)
Green
Black/Red

Relay 5 – Changeover thru 73 (these match)
Green/Brown
Green/Brown
Black
Brown

Relay 6 – Hazard and Turn Signal thru 73 (these match)
Green/Yellow (2)
Black/White
Green/Violet
Brown (2)


My 73 1/2 wire colors matched the early coupe diagram except for the window load shed relays which do not match the 74 diagram.

 

[HB Chris]

1974 wire colors:

Relay 1 Wiper/Wash
Brown/Red
Black
Black
Brown/Black
Black/Red
Black/Blue
Brown (3)

Relay #2 Load Shed
Red (2)
Brown (3)
Green (2)
Green/Violet

Relay #3 Window Load Shed
Green Red (2)
Red
Brown/Black
Red (2)

Relay #4 Window Load Shed
Green/Red
Brown (2)
Green
Red (2)

Relay #5 Changeover (the 74 does not have one as the A/C fan switch has an added pin making it not needed)

Relay #6 Hazard/Turn
Green Yellow
Black/Whit
Green/Violet
Brown


As the fuse block changed in 74 along with wires, wire diameter, added items (flashlight, etc.) our coupes can be very different but I never knew how much. If someone wants to very that their 74 matches what I have posted from the diagram that would be great. I don't know if I want to tackle the 2800CS as I don't have enlarged copies.

 

[Roger S]

Thank you, Chris. Just getting to the board after a few days. Trying to install the front and rear glass in both coupes today but the weather did not participate. With respect to your post, Carl (LaJolla) responded to a TA picture and identified the additional relays and plugs as part of the old automatic transmission configuration.

I appreciate the FaceTime assist with sorting the wire nest under the column and the air box concern re placement and clearance. As always, you rock.

 

[Bwana]

Outstanding info! Now we just need it for a '72 CSi

 

[HB Chris]

Everything for the 73 also applies to the 72 and earlier 3.0CS, only window load shed relays were added in mid-73.