2019-2024 Ford Edge & Lincoln Nautilus Left Power Liftgate Motor Guide
Diagnosing and replacing the left-side power liftgate motor (KT4Z-14B351-A) on your Ford Edge or Lincoln Nautilus, including common software issues and TSBs.
- This part is the LEFT (driver's side) power liftgate motor, OEM part number KT4Z-14B351-A.
- Many failures are software-related. Before replacing the motor, check for TSBs (like 19-2104, SSM 50071) that require a module reprogram.
- DTC B144F:79 often points to a software calibration issue, not a bad motor. Ford advises reprogramming the module first.
- After replacement, a 'Power Liftgate Initialization' (reset) is required, which can be done by disconnecting the battery or pulling the correct fuse.
Symptoms of a Failing Left Liftgate Motor
When the left-side power liftgate motor begins to fail, you may notice one or more of the following symptoms. Because many issues can also be caused by software glitches, it's important to pay close attention to the specific behavior.
- Liftgate is Inoperative: The most common symptom is the liftgate failing to open or close with any of the switches (dash, key fob, or liftgate button). You may hear the latch unlock, but the liftgate itself does not move.
- Grinding or Popping Noises: A grinding noise during operation often points to a stripped gear inside the motor housing. A popping or snapping noise on 2019 models may be related to a separate TSB for the reversing lamp close-out panel interfering with the liftgate.
- Liftgate Opens/Closes Partially: The gate may start to move but then stop or reverse direction. This can be a sign of a weak motor, a faulty position sensor within the motor assembly, or a software issue.
- "Liftgate Ajar" Warning Light: While often related to the latch, a TSB for early 2019 models indicates that a software issue in the liftgate module can cause this warning to appear, sometimes accompanied by a dead battery.
- Associated OBD-II Trouble Codes: A scan tool may reveal specific Diagnostic Trouble Codes (DTCs) stored in the Rear Gate Trunk Module (RGTM). Common codes include B144F:79 (Motor of Tailgate/Liftgate), which can point to the motor itself or a software problem, and B144E:29 (Position Sensor 2 of Tailgate/Liftgate), which indicates a fault within the strut's internal sensor.
Known Issues, TSBs, and Recalls
Several Technical Service Bulletins (TSBs) and Special Service Messages (SSMs) have been issued for the power liftgate system on these vehicles. Many problems that seem like a failed motor are actually software-related and may only require reprogramming the control module.
| TSB / SSM Number | Vehicles Affected | Issue | Solution |
|---|---|---|---|
| TSB 19-2104 | 2019 Edge/Nautilus built on or before Nov 14, 2018 | Discharged battery, interior lights cycling, or a "Liftgate Ajar" message. This is caused by the RGTM module staying awake. | Reprogram the Rear Gate Trunk Module (RGTM) with the latest software. | 🎬 See how this software glitch causes battery drain issues.
| SSM 50071 | 2019-2021 Edge/Nautilus | Power liftgate is inoperative, sometimes with DTC U3000:49 stored in the RGTM. | Reprogram the RGTM. |
| SSM 49267 | 2019-2020 Edge/Nautilus | Inoperative power liftgate with DTC B144F:79. This is often due to a module calibration issue, not a failed motor. | Reprogram the RGTM. The bulletin specifically states not to replace the motor unless the code remains after reprogramming. |
| TSB 19-2224 | 2019 Edge built on or before March 6, 2019 | A popping or snapping noise when opening or closing the liftgate. This is caused by interference from the reversing lamp close-out panel tabs. | Replace the left and right reversing lamp close-out panels with updated parts. | 🎬 Watch: How to fix the popping noise on 2019 models.
Important: Before replacing the liftgate motor for an inoperative condition, it is highly recommended to have a dealer or qualified shop check for any applicable software updates for the Rear Gate Trunk Module (RGTM). Many liftgate problems on these vehicles are resolved with a simple reprogram.
Buying a Used Left Liftgate Motor
When purchasing a used OEM liftgate motor (part number KT4Z-14B351-A), you are getting the same quality part that was installed at the factory. This is often a better choice than cheaper aftermarket alternatives, which may lack the precise calibration and durability of the original. Here’s what to look for:
- Verify the Part Number: Ensure the part is a genuine Ford KT4Z-14B351-A. This is the left (driver's) side motor. The right side has a different part number and is not interchangeable.
- Physical Inspection: Check the motor housing for any cracks or signs of heavy impact. Inspect the electrical connector for corrosion or bent pins. Look at the ball joints on each end to ensure they are not excessively worn or damaged.
- Source Vehicle Information: If possible, get the mileage and year of the vehicle the part came from. A part from a lower-mileage, later-model-year vehicle is always preferable.
- Ask About Functionality: Ask the seller if the part was tested or if the liftgate was functional before the part was removed. While not always possible, it provides extra assurance.
Cost Breakdown
Prices can vary based on location and supplier, but here is a general cost comparison for the left power liftgate motor.
| Part Type | Estimated Cost |
|---|---|
| New OEM (Dealer) | $430 - $530 |
| New OEM (Online) | $260 - $270 |
| New Aftermarket | $90 - $170 |
| Used OEM | $100 - $200 |
| Shop Labor for Replacement | $100 - $200 |
| Shop Labor for Module Reprogramming | $75 - $150 |
Programming and Initialization
Pro Tip: After replacing the motor or performing any related service, a Power Liftgate Initialization (reset) procedure is required.
A full reset can often be accomplished by disconnecting the negative battery terminal for at least one minute. However, this will also reset other vehicle systems like radio presets and adaptive transmission learning. A simpler method is to locate and pull the specific fuse for the power liftgate module, wait 20-30 seconds, and reinstall it. After restoring power, you may need to cycle the liftgate manually once or set the open height for the system to re-learn its position.
🎬 Watch: Pro tips for resetting your Ford liftgate module.For software-related TSBs, a dealer or a shop with a Ford-compatible J2534 diagnostic tool is required to reprogram the RGTM. This is not a DIY procedure for most owners.
Frequently Asked Questions
Do I need to replace both the left and right motors at the same time?
No, it is not necessary to replace both motors if only one has failed. They are sold and can be replaced individually. However, if one has failed due to age and high usage, the other may not be far behind.
My liftgate unlocks but won't move. Is it the motor?
It could be the motor, but it is very likely a software issue. For the 2019-2021 Ford Edge and Lincoln Nautilus, multiple service bulletins (SSM 50071, SSM 49267) address this exact symptom, which is often fixed by reprogramming the Rear Gate Trunk Module (RGTM). Always investigate software updates before replacing hardware.
Can I install this part myself?
Yes, the physical replacement is straightforward for a DIY mechanic. It involves removing some interior trim panels and unclipping the motor from its ball-joint mounts at the top and bottom. However, remember that a power liftgate initialization procedure will be necessary after installation.
What is the difference between this motor and a regular liftgate strut?
A regular liftgate strut is just a gas-pressurized cylinder that assists in lifting the gate and holding it open. This part is a motorized actuator; it contains an electric motor, gears, and a position sensor all in one unit. It actively pushes the liftgate open and pulls it shut, which is why it is much more complex and expensive than a simple gas strut.
Helpful Videos
Technical Specifications
OEM Part Numbers: KT4Z-14B351-A KT4Z14B351A
Position: Left (Driver's Side). Type: Motorized Spindle Drive / Power Cylinder. For vehicles with a power liftgate only.
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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Ford Edge:
- Lincoln Nautilus: