John Kohler
Active Member
This is a long shot, but my power seats will not operate if the rear hatch is open and the doors are locked.
2014 Ford Expedition XL Adding Third Row
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Trainmaster
Old School Member
Good to see you've got the connector pins figured out.
If all else fails, and you don't want to mess around with re-discovering and installing any computerized door-open-interlock logic circuitry designed into this thing, you may have to just find the power lead and wire it to an unused fuse.
If you really want to stretch your sills, you can learn about Forscan and see if the optional logic can be programmed into the truck's computer. I have no idea how Ford interlocks the seats, but Forscan's spreadsheets posted on the Internet would be one place to explore.
It's a long shot, because Ford's documentation of optional accessories is somewhat sketchy, but the shop manual may discuss the logic in any pinpoint diagnostic charts provided for troubleshooting the seats.
My how things have changed!
If all else fails, and you don't want to mess around with re-discovering and installing any computerized door-open-interlock logic circuitry designed into this thing, you may have to just find the power lead and wire it to an unused fuse.
If you really want to stretch your sills, you can learn about Forscan and see if the optional logic can be programmed into the truck's computer. I have no idea how Ford interlocks the seats, but Forscan's spreadsheets posted on the Internet would be one place to explore.
It's a long shot, because Ford's documentation of optional accessories is somewhat sketchy, but the shop manual may discuss the logic in any pinpoint diagnostic charts provided for troubleshooting the seats.
My how things have changed!
I think the circuit board is fine, I checked the part number, 7L1T14B476A, and it is used on other Expeditions with a third row. I'm thinking more and more this is a computer issue that needs to be adjusted either by resetting the SJB (smart junction box, passenger side fuse box) or adding it via FORScan.
Trainmaster
Old School Member
Keep us advised. Interesting stuff.
So I brought it to the dealer, explained my situation, and they at first didn't really know what to do. So the service manager was called over, and I explained again, he basically said it isn't a module you can turn on or off, and that Ford themselves would control most of the codes, but he was very curious about the vehicle, and decided to grab a computer, hook it up and see what he could do. This is him on the computer, after it first getting connected:
He went through, and didn't see anything of note that included the third row. He started to disconnect everything, and I asked: "What if we just reboot (not a reboot, like disconnect the battery, but a reset of the computer itself, and its memory) the SJB/GEM?" He said that would be fine, warned me of the risks, but reconnected, and did that. I heard the SJB make all sorts of clicking noises (relays), and this is EXACTLY what I wanted to hear. We opened the rear hatch, to see if that did the job...
AND IT DID!
Here the manager is, (he had just given me a thumbs up, and I got permission to post his photo):
Here is the guy I first talked to, that got the manager involved, after I told him we just did something never before done on an Expedition (just after I got his permission to post his photo):
An hour later, after buttoning up the wiring, here is the install before reassembly and install of the seats:
Continuing because I've reached limit of uploads in next forum post.
He went through, and didn't see anything of note that included the third row. He started to disconnect everything, and I asked: "What if we just reboot (not a reboot, like disconnect the battery, but a reset of the computer itself, and its memory) the SJB/GEM?" He said that would be fine, warned me of the risks, but reconnected, and did that. I heard the SJB make all sorts of clicking noises (relays), and this is EXACTLY what I wanted to hear. We opened the rear hatch, to see if that did the job...
AND IT DID!
Here the manager is, (he had just given me a thumbs up, and I got permission to post his photo):
Here is the guy I first talked to, that got the manager involved, after I told him we just did something never before done on an Expedition (just after I got his permission to post his photo):
An hour later, after buttoning up the wiring, here is the install before reassembly and install of the seats:
Continuing because I've reached limit of uploads in next forum post.
Last edited:
Now to fix a few wiring issues from its former life of a Fire Station vehicle, and seats will be going in. I will probably not document the seats being installed, because that part is the same with or without the third row. In the end, I asked the manager what exactly he did, and he said:
"I cleared the KAM (keep alive memory), cleared codes in the SJB (smart junction box)/GEM, and ran the self test just on the SJB which cased the relays to click."
I hope this helps future "third row enthusiasts".
Trainmaster
Old School Member
Sounds like when rebooting, it recognized the module. Well that's interesting.
star-art
Full Access Members
The SJB enables and disables the relay for the 3rd Row Power-Fold Seats. There's also a Liftgate/Trunk Module (LTM) for vehicles with Power Liftgate, but since he got his to work without retrofitting that (unless I missed something), it tells us serial communication between the SJB and LTM apparently isn't needed for this to work.
It's quite possible the 3rd Row Seat Enable FET on pin 24 of C2280C of the SJB has to enabled in firmware. Apparently the reset done by the dealer somehow accomplished this.
At any rate, I'm glad to hear you got it working!!! For anyone else reading this thread and thinking about doing this, here's some additional info that might help:
There are two different control setups for the 3rd Row Power-Fold Seats. These controls are not swappable or compatible since the Body Control Module in 2015-17 was programmed differently than the SJB from 2007-14.
In all years, the 3rd Row Power seats were paired with the Power Liftgate feature.
The seats will operate only if the vehicle is in Park and the rear liftgate is open. This is to help prevent any mishaps where the seat might move with someone sitting in it. (It's no guarantee, but that's what Ford came up with.) If you retrofit 3rd row power seats into your vehicle, for safety as well as liability reasons be sure to wire it up to factory specs and don't try to bypass the SJB/BCM control of the relay.
Since you got yours to work with (what I'm assuming is) a standard liftgate, that tells me the SJB is looking at the decklid ajar input as well as the transmission status to determine whether to enable the 3rd Row Power-Fold Seat Relay. Thankfully, 2007-14 vehicles with a Liftgate Module (LTM) have a dedicated output for Decklid Ajar. This is what made it possible for you to retrofit 3rd Row Power-Fold Seats without also adding the Power Liftgate feature at the same time.
For 2007-14, you press and hold the switch to move the seats. Starting in 2015, this entire setup changed and the switches became momentary where one brief press in either direction moves the seats all the way open or closed. This means the 2015-17 BCM is programmed completely differently. It also means newer style switches won't work in older vehicles without adding some custom electronics.
Hope that helps!
It's quite possible the 3rd Row Seat Enable FET on pin 24 of C2280C of the SJB has to enabled in firmware. Apparently the reset done by the dealer somehow accomplished this.
At any rate, I'm glad to hear you got it working!!! For anyone else reading this thread and thinking about doing this, here's some additional info that might help:
There are two different control setups for the 3rd Row Power-Fold Seats. These controls are not swappable or compatible since the Body Control Module in 2015-17 was programmed differently than the SJB from 2007-14.
In all years, the 3rd Row Power seats were paired with the Power Liftgate feature.
The seats will operate only if the vehicle is in Park and the rear liftgate is open. This is to help prevent any mishaps where the seat might move with someone sitting in it. (It's no guarantee, but that's what Ford came up with.) If you retrofit 3rd row power seats into your vehicle, for safety as well as liability reasons be sure to wire it up to factory specs and don't try to bypass the SJB/BCM control of the relay.
Since you got yours to work with (what I'm assuming is) a standard liftgate, that tells me the SJB is looking at the decklid ajar input as well as the transmission status to determine whether to enable the 3rd Row Power-Fold Seat Relay. Thankfully, 2007-14 vehicles with a Liftgate Module (LTM) have a dedicated output for Decklid Ajar. This is what made it possible for you to retrofit 3rd Row Power-Fold Seats without also adding the Power Liftgate feature at the same time.
For 2007-14, you press and hold the switch to move the seats. Starting in 2015, this entire setup changed and the switches became momentary where one brief press in either direction moves the seats all the way open or closed. This means the 2015-17 BCM is programmed completely differently. It also means newer style switches won't work in older vehicles without adding some custom electronics.
Hope that helps!
star-art
Full Access Members
The SJB *should* be the same for all models as that would save Ford money over making dedicated hardware so it makes logical sense. The SJB has some computer firmware in it that allows for configuring different options.
If it can't be re-flashed for any reason, you might be able to swap your SJB with one from a Limited or King Ranch. These models had the 3rd Row Power-Fold as standard.
But, before doing anything else, you need to get a factory service manual (FSM). It will contain detailed diagnostic instructions for chasing down problems with the Power-Fold setup.
If it can't be re-flashed for any reason, you might be able to swap your SJB with one from a Limited or King Ranch. These models had the 3rd Row Power-Fold as standard.
But, before doing anything else, you need to get a factory service manual (FSM). It will contain detailed diagnostic instructions for chasing down problems with the Power-Fold setup.
