willalex09
Active Member
Why Retrofit Upfitter Switches?
Much like the guide that I did for retrofitting upfitter switches in my 2015 expedition (https://www.expeditionforum.com/threads/upfitter-switch-retrofit-guide.56813/), the purpose of this guide is to outline the process of retrofitting upfitter switches to control additional accessories, such as a roof light bar, rear lights, and a train horn.
I wanted switches mounted on the overhead console because, honestly, they just look awesome up there. Unfortunately, I didn’t find any aftermarket options that fit the look I wanted—they all seemed a bit “tacky” to me. This project aims to blend utility with style, creating a setup that feels like it rolled off the assembly line. Of course, your tastes may vary, but this guide is here to help you achieve a sleek and functional installation.
Materials Needed
To get started, gather the following components:
Installing & Mounting
Mounting the Switch Assembly
The overhead console offers the perfect spot, and for this project, I used the sunglasses holder. Since I don’t use it anyway, it was a no-brainer.
In the engine bay, there’s a convenient spot above the factory fuse box on the passenger side. The upfitter fuse/relay box fits perfectly here with a friction fit, allowing easy removal when accessing the factory fuse box.
Wiring Modifications
Since the upfitter switches are designed for Super Duty trucks, some modifications are necessary to make the wiring compatible with the Expedition. Here’s how I handled the wiring for both the upfitter harness and fuse/relay box harness.
Upfitter Wiring Harness
This harness connects the switches to the relay box. I cut off the connector and extended the wires using the 18-gauge, 8-conductor wire.
NOTE: I cut this harness and added the 8-conductor wire in the middle and then soldered 1 foot or so of the original wires on the end so that the colors would match up inside of the engine bay. If you just extend new wires onto the end of the harness, make sure to keep track of what color went to what color of “new wire”.
After that, route the wires from the overhead console, along the headliner, down the A-pillar, through the firewall, and into the engine bay.
Upfitter Switch Assembly Connector Wire Pinout:
Bundle 1 (Gets extended and run into the engine bay)
Similar to the previous harness, I did not require all the wires included in this one. I carefully removed the tape, reorganized the wiring to suit my specific needs, applied protective measures, and re-taped the harness. The unused wires were securely taped, and I created separate wire bundles (excluding the power cable) for the wires that will be utilized.
Power Cable:
This harness came with a 164ft power cable as it has to run clear across Montana to in the super duty trucks lol. I trimmed it down to 2 ft and added a new ring terminal and bent it 90 degrees for a clean fit to the battery.
Wire Bundle 1 (Relay Activation)
- Yellow – Upfitter Relay 1 Trigger
- GN-BN – Upfitter Relay 2 Trigger
- VT-GN – Upfitter Relay 3 Trigger
- BN – Upfitter Relay 4 Trigger
- BU-OG – Upfitter Relay 5 Trigger
- YE-OG – Upfitter Relay 6 Trigger
- GN-OG – In a super duty, this would go to a “Hot in Run” output of the BCM. This controls relays 1-4.
- GN-RD - In a super duty, this would go to a “Always Hot” output of the Upfitter Relay Box. This controls relays 5-6.
- If these 2 wires are connected to a constant power source, the switches will activate accessories regardless of whether the vehicle is running. Alternatively, connecting them to an "ignition-on" (hot-in-run) power source will ensure the switches activate accessories only when the vehicle is turned on. In this case, I opted to connect both wires to a constant 12V power source, enabling the switches to power accessories regardless of the vehicle's operational state.
Wire Bundle 2 (Ground)
This is my ground bundle. I consolidated all the black ground wires by soldering them together into a single, thicker wire, and then attached a ring terminal for connection to a factory ground point by the battery.
Wire Bundle 3 (Relay Output/Accessory Power)
This is my relay output bundle, which consists of the wires that receive power when the corresponding switches are activated. These wires serve as connection points for the power leads of any accessories being installed.
- BN-GN – Relay 1 Output
- VT-OG - Relay 2 Output
- BU-GN - Relay 3 Output
- GY-BN – Relay 4 Output
- BN-BU – Relay 5 Output
- GY-OG - Relay 6 Output
Final Thoughts
This project took about 4–5 hours (plus a few Irish Reds and breaks to play with the dogs). The end result? A fully functional, factory-looking switch setup that blends seamlessly with the interior. The illuminated, dimming switches perfectly match the rest of the cabin, making it look like it was always meant to be there.
Happy modding! Let me know if you have questions or tips for your own build
Much like the guide that I did for retrofitting upfitter switches in my 2015 expedition (https://www.expeditionforum.com/threads/upfitter-switch-retrofit-guide.56813/), the purpose of this guide is to outline the process of retrofitting upfitter switches to control additional accessories, such as a roof light bar, rear lights, and a train horn.
I wanted switches mounted on the overhead console because, honestly, they just look awesome up there. Unfortunately, I didn’t find any aftermarket options that fit the look I wanted—they all seemed a bit “tacky” to me. This project aims to blend utility with style, creating a setup that feels like it rolled off the assembly line. Of course, your tastes may vary, but this guide is here to help you achieve a sleek and functional installation.
Materials Needed
To get started, gather the following components:
- Upfitter Switch Assembly(Ford HC3Z-13D730-AA)
- Chosen for its interior light matching the 2022 Expedition, ensuring a seamless look.
- Wire Assembly(Ford HC3Z-15A404-B)
- Needed for the connector that plugs into the switch assembly.
- Fuse & Relay Box Harness(Ford HC3Z-14A303-F)
- Designed for 2017-2019 Super Duty trucks.
- 18-Gauge 8-Conductor Electrical Wire
- Additional wiring supplies: 12-, 14-, 16-gauge wire, connectors, solder, heat shrink tubing, etc.
Installing & Mounting
Mounting the Switch Assembly
The overhead console offers the perfect spot, and for this project, I used the sunglasses holder. Since I don’t use it anyway, it was a no-brainer.
- Remove the overhead console.
- Take out the sunglasses holder and cut a hole just large enough for the switches to fit snugly.
- Use CA glue with an activator for initial mounting, then reinforce with thicker CA glue to ensure everything stays in place. After curing, it’s rock-solid!
In the engine bay, there’s a convenient spot above the factory fuse box on the passenger side. The upfitter fuse/relay box fits perfectly here with a friction fit, allowing easy removal when accessing the factory fuse box.
Wiring Modifications
Since the upfitter switches are designed for Super Duty trucks, some modifications are necessary to make the wiring compatible with the Expedition. Here’s how I handled the wiring for both the upfitter harness and fuse/relay box harness.
Upfitter Wiring Harness
This harness connects the switches to the relay box. I cut off the connector and extended the wires using the 18-gauge, 8-conductor wire.
NOTE: I cut this harness and added the 8-conductor wire in the middle and then soldered 1 foot or so of the original wires on the end so that the colors would match up inside of the engine bay. If you just extend new wires onto the end of the harness, make sure to keep track of what color went to what color of “new wire”.
After that, route the wires from the overhead console, along the headliner, down the A-pillar, through the firewall, and into the engine bay.
Upfitter Switch Assembly Connector Wire Pinout:
Bundle 1 (Gets extended and run into the engine bay)
- Yellow: Upfitter Relay 1 Trigger
- GN-BN: Upfitter Relay 2 Trigger
- VT-GN: Upfitter Relay 3 Trigger
- BN: Upfitter Relay 4 Trigger
- BU-OG: Upfitter Relay 5 Trigger
- YE-OG: Upfitter Relay 6 Trigger
- GN-OG – In a super duty, this would go to a “Hot in Run” output of the BCM.
- GN-RD - In a super duty, this would go to a “Always Hot” output of the Upfitter Relay Box.
- BK-WH – gets spliced into the Black (Ground) wire of the overhead console connector.
- VT-GY – Gets spliced into the VT-GY (Illumination) wire of the overhead console connector.
Similar to the previous harness, I did not require all the wires included in this one. I carefully removed the tape, reorganized the wiring to suit my specific needs, applied protective measures, and re-taped the harness. The unused wires were securely taped, and I created separate wire bundles (excluding the power cable) for the wires that will be utilized.
Power Cable:
This harness came with a 164ft power cable as it has to run clear across Montana to in the super duty trucks lol. I trimmed it down to 2 ft and added a new ring terminal and bent it 90 degrees for a clean fit to the battery.
Wire Bundle 1 (Relay Activation)
- Yellow – Upfitter Relay 1 Trigger
- GN-BN – Upfitter Relay 2 Trigger
- VT-GN – Upfitter Relay 3 Trigger
- BN – Upfitter Relay 4 Trigger
- BU-OG – Upfitter Relay 5 Trigger
- YE-OG – Upfitter Relay 6 Trigger
- GN-OG – In a super duty, this would go to a “Hot in Run” output of the BCM. This controls relays 1-4.
- GN-RD - In a super duty, this would go to a “Always Hot” output of the Upfitter Relay Box. This controls relays 5-6.
- If these 2 wires are connected to a constant power source, the switches will activate accessories regardless of whether the vehicle is running. Alternatively, connecting them to an "ignition-on" (hot-in-run) power source will ensure the switches activate accessories only when the vehicle is turned on. In this case, I opted to connect both wires to a constant 12V power source, enabling the switches to power accessories regardless of the vehicle's operational state.
Wire Bundle 2 (Ground)
This is my ground bundle. I consolidated all the black ground wires by soldering them together into a single, thicker wire, and then attached a ring terminal for connection to a factory ground point by the battery.
Wire Bundle 3 (Relay Output/Accessory Power)
This is my relay output bundle, which consists of the wires that receive power when the corresponding switches are activated. These wires serve as connection points for the power leads of any accessories being installed.
- BN-GN – Relay 1 Output
- VT-OG - Relay 2 Output
- BU-GN - Relay 3 Output
- GY-BN – Relay 4 Output
- BN-BU – Relay 5 Output
- GY-OG - Relay 6 Output
Final Thoughts
This project took about 4–5 hours (plus a few Irish Reds and breaks to play with the dogs). The end result? A fully functional, factory-looking switch setup that blends seamlessly with the interior. The illuminated, dimming switches perfectly match the rest of the cabin, making it look like it was always meant to be there.
Happy modding! Let me know if you have questions or tips for your own build
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