B104A on Jeep: How to Diagnose & Fix
Mode Door (Floor/Defrost) Travel Range Too Small
1 Jeep model · 1 documented issue · 1 critical · $350-$1,400 repair
B104A on Jeep by model: symptoms, diagnosis and fix
The Grand Wagoneer's power cinch tailgate latch mechanism, which uses an electric motor to fully close and seal the rear liftgate, has been reported to fail in both directions — either not cinching closed or not releasing when the open button is pressed. The electric cinch latch assembly can develop motor failures or the latch pawl can bind, leaving owners unable to open or securely close the tailgate. Multiple NHTSA complaints reference the tailgate appearing closed but unlatching while driving.
Common Symptoms
- Tailgate will not fully close or cinch shut
- Tailgate opens unexpectedly while driving
- Power liftgate button unresponsive to open or close command
- Grinding noise from tailgate latch area during operation
- Warning chime and 'Liftgate Open' message while gate appears closed
How to Fix
Replace the power cinch latch assembly on the tailgate with updated Mopar latch unit (part referenced in TSB coverage for WS-platform liftgate). Inspect and lubricate latch striker alignment before replacement, as misalignment causes premature latch motor wear. Dealers have performed this under warranty on affected vehicles.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Mopar 68364385AE liftgate latch/lock actuatorOEMMopar 68364385AE
Liftgate latch/actuator replacement after electrical, alignment and obstruction checks confirm the latch assembly failed Fitment/availability: 2022-2025 Jeep Grand Wagoneer 3.0L or 6.4L liftgate latch. Confirm VIN/current supersession; n…
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B104A code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does B104A mean on a Jeep?
B104A stands for "Mode Door (Floor/Defrost) Travel Range Too Small." B104A is a manufacturer-specific body code that, in common HVAC applications, indicates the climate control module measured too small a travel range for an air-distribution (mode) door during actuator calibration, typically the floor/defrost blend-mode door. This means the door is not moving through its full expected range, so air may not direct correctly between the floor, vents, and defrost outlets. It is a comfort-system issue and does not affect drivability. Because the meaning is maker-specific, confirm against your vehicle's service data. On Jeep it is documented across 1 model: Grand Wagoneer.
What are the most common causes of B104A?
The most common causes of B104A are: Seized, binding, or obstructed mode (air distribution) door, Faulty mode door actuator (stepper motor), Broken or disconnected door linkage, Open or short in the actuator drive circuit, Corroded or loose actuator connector, Foreign object blocking the door's travel. The specific cause varies by vehicle.
How much does it cost to fix B104A on a Jeep?
Published repair estimates on Jeep range from $350 to $1,400 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for B104A on a different make?
View B104A across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.