REPLACING THE LEFT THIRD SEAT LATCH ASSEMBLY ON A 2007 MERCURY OR FORD
Take off the rear access cover and trim pieces:
- Open the rear floor access cover and remove the four screws and it will come off.
- Remove one screw at the back of each side trim piece and towards the front of each trim piece is a plastic plunger, you can use a crowbar and yank them out. Both trim pieces can be taken out. Note that you may need to remove one more screw holding the trim down before the trim comes loose.
Remove the third row seats:
- Take out the two bolts in the rear and one nut in the front on each side of the seat unit.
- Remove the screw holding down the seat bracket and “D” loop in the middle front of the seat unit.
- Remove the two large nuts at the rear of the seat unit, it is holding down the seat latch assemblies between the two seats.
- Be sure to unplug the harness going to the two motors.
The seat unit can now be taken out of the vehicle. I was able to slide the seat assembly onto a cart using a piece of plywood. I used this as my workbench and away from the vehicle.
My next step was to loosen the right hand seat to separate them so I could get to some of the fasteners holding the latch assembly to the left seat. You do not need to remove the seat entirely since it is still held in place to the frame with pop rivets, but it will move out of the way enough to work on the left seat.
To get the RH seat loose:
- There are two nuts holding the seat to the front rail. These nuts are not easy to get to and are very tight, possibly with Locktite. I used a 1/2” box wrench and they took a good 10 min. to remove.
- Next, using a 1/2” drive socket, I removed two nuts that hold the two latch assemblies to the middle rail. Note that the right seat bracket is on top of the left one. One nut is easy to get to; the other requires that one of the seats be in the upright position. I was able to hook up an external battery (using an emergency jump-start unit) to the motor harness and applied power to the motor connector using clip leads. Just trace the wire color-codes. You can change directions by reversing the leads.
- The RH seat can now be moved aside enough to get access to the rest of the fasteners holding the latch assembly to the seat.
Here are the final steps to get the latch assembly out; up to now it’s not been that difficult. To finish taking the latch assembly out:
- Remove the large 3/4” nut holding the seat belt latches, and slide them out. The nut has a copper washer/bushing; it comes out with the belt latches. These have to come out before you can get access to the screw in step #4.
- Take off the small plastic cover over the side of the seat back. Two 5/16” screws hold it in place.
- There are two 1/2” bolts holding the assembly arm to the seat back. One is easy to get to; the other one is not accessible without cutting the seat cover over the bolt. It might be possible to pull the cover up out of the way, but I found it easier to just slice the seam on the back of the cover about two inches to expose the bolt head. These two bolts are tight, again, possibly with Locktite, and does take a lot of torque to get them started. I finally used a short pipe extension over a socket handle to get enough leverage.
- The next step is easy if your seat back is upright, but there’s a large flat screw with a bushing just below the latch assembly that requires a #30 torx driver. There’s not enough room for the driver if the seat is down. Since my seat was down, I had to use a pair of vice grips to remove it.
The latch assembly is now free. Boy that was fun… however, now that you know what you did to take it apart, putting it back together will be a lot easier.
After checking the operation of the new assembly out by plugging it in the vehicle, here are the steps I used to get it back in. Note that when I raised and lowered the seat backs I used an external battery connected to the motor harness with clip leads.
Securing the assembly:
- I first fastened the two bolts that hold the seat back to the assembly arm. I sprayed a little WD-40 on the screws to make them drive easier and they went in easier than they came out.
- I lowered the RH seat and I was now able to raise the LH seat to make the flat torx screw accessible.
- Using a #30 torx driver, replace the flat-head screw holding the assembly to the back of the seat. Make sure that the bushing rides inside the assembly bracket. Don’t do this with the seatback up, otherwise you’ll have to use vice grips or pliers.
- At this point, it’s OK to repair the seam you cut in the back seat cover. Since it is sewed from the inside, I opted to glue it with all-purpose cement; I aligned the seams and secured it with duct tape until the glue dried.
- Align the two seatbelt latches to the stud and fasten tight using the 3/4” nut. The thin bass washer/bushing was too deformed for me to reuse, so I replaced it with a flat washer. That seemed to work OK. When done right, they will move down when the seat back goes down and spring back when it goes up.
- Align the LH assembly bracket onto the two threaded stud on the seat frame then place the RH bracket on top of it. I had to raise the RH seat to get it to go onto the studs. It’s a bit tricky, but it does go in.
- Tighten a 1/2” nut onto each stud. Make sure the two mounting holes on each bracket line up; otherwise, you’ll have to loosen the nuts later to get the seat assembly in properly.
- Lower both seats, and then flip the seat assembly on its back.
- Make sure the two studs on the front of the seat frame are aligned to the bracket underneath the RH seat. Mine had slipped in place while I was connecting the two brackets to the rear of the seat frame. Use two 1/2” nuts to connect the two. I had to use a box wrench, the same way I took them off, but I put some oil on them first to make it a bit easier.
The seats are ready to be put back in the vehicle.
Simply follow the reverse of what you did to take the seat out.
- Align the seats with the studs, two in front and two between the latch assemblies in the rear.
- Reconnect the motor harness.
- Tighten all the screws and nuts that hold the seats in place, two screws and one nut on each side of the seats, two nuts between the seats in the rear latch assemblies, and one large screw in the front holding the “D” ring to the floor. The seats must be raised to get to the front screw.
- Replace the two side trim pieces and the back access door and you’re good to go.
Oh yeah, I did have two small screws left over and I believe they’re from the two side trim pieces, but since everything was back together, I just left things the way they were.
Just another note, if the seats won’t move when you connect them to the harness, close all the doors and hatch for a minute or so and try again. There is an override timer that disconnects power if the doors are open too long.
Total time for this project was about four and one-half to five hours. That’s for one person doing everything with no assistance, and a very senior citizen at that. Knowing the above steps should reduce that time by at least an hour. An experienced Ford mechanics with the right tools, agility and knowledge and who is being paid to work reasonably fast should be able to do this job in around 2-3 hours. That’s just my guess based on how long I took, my age and not ever having done this before.