Ford uses what is called an anti-slosh or slosh module to dampen the signal from fuel level sensor in the gas tank to the fuel gauge in the dash. Without this module, the fuel gauge will bounce and move whenever the fuel level sensor float moves in the tank. This can be in acceleration, braking, turning, going up or down hills or any combination of them. This can be quite distracting and also is not how OEM cars work.
The anti-slosh or slosh module is a printed circuit board located in the instrument panel. Since the Factory Five cars are based on a 1987-1993 Mustang, this is where I got my anti-slosh module. Other Ford vehicles have the same module and there are other modules that work in the same manner for other late model Fords.
This is what the module looks like.
This version of the module slides into the back of the instrument panel into a slot which then allows the module to make contact with the circuit panel on the back of the panel.
The first thing that I needed to do was to get the wiring diagram for the slosh module so I could figure out the function of each of the modules contacts. Here is the wiring for a 1993 Mustang.
Buy tracing the printed circuit on the back of the instrument panel, I could find where they ended up. They ended up going to another connector in the dash. This connector when to the body wiring harness. This is the pinout for that connector.
The connectors in question turned out to be 1,2 and 4 which are highlighted in red. You can see this by looking at the printed circuit. The pinout numbers for both the harness connector and the anti-slosh module are placed on the picture.
Knowing this, I first removed the contact unit on the module. I did this by removing the plastic piece by first prying the contacts out of the plastic and then removing the contacts with a soldering iron.
This leaves the holes for me to solder in some new wires.
The wires will connected as follows:
4. Fuel Level Sender - This is the OEM Ford one located in the fuel tank.
S. Fuel Gauge Sender Feed - This is wire that goes to the sender feed on the fuel gauge itself.
1. +12V - A power source that is hot in start or run and is protected with a 15A fuse.
How this is finished and mounted is dependent on the builder wants to accomplish it. The module should be protected by something that will not allow the circuit board to be touched by anything that could carry electricity. I plan to find a plastic box at the local electronics shop and mount it in there and have the wires exit the box to a connector. The connector will then plug into its mate which will be wired into the main body harness of myCoupe.
UPDATE - CONNECTOR
I found a set of connectors that will solder directly into the holes of the OEM connection. You can purchase these from Digi-Key Digi-Key.
The parts consist of:
Molex 7 position Connection Header (26-48-1071)
Digi-Key Part Number WM4405-ND
Molex 7 position Connection Housing (09-50-7071)
Digi-Key Part Number WM1569-ND
Molex connection Terminal (08-50-0106)
Digi-Key Part Number WM2300-ND
The first thing to do is to remove the two pins from the header that don't have a hole in the circuit board. You can remove the pins by using needle nose pliers. Grab the pin with the pliers and gently pull on the pin. Use more force until the pin slides out. You can tell which pins to remove and the alignment of the header by looking at the following image.
Then place the header into the board making sure its feet are flat against the circuit board. Then apply some water based soldering paste on the ends of the pins and using a soldering iron, apply silver solder to the pins.
You then take the housing and five pins and start the process of wiring the housing.
Using the wiring diagram from the 1993 Ford Mustang, you end up with a final product. To make the connector more secure, you put an empty connector to match the pin that is not used.
All that would be left to do is to place the unit in a plastic box or cover the bottom with epoxy and secure it.