B104A on 2021-2024 Jeep Grand Wagoneer — Mode Door (Floor/Defrost) Travel Range Too Small
1 vehicles · 1 makes · $350-$1,400 repair
Most Reported On
B104A is an OBD-II diagnostic trouble code meaning “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. This code is most commonly reported on 2021-2024 Jeep Grand Wagoneer, with repair costs ranging from $350 to $1,400.
Common Causes
Typical Repair Cost
Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose B104A, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
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FAQ
What does B104A mean?
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.
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?
Repair costs for B104A range from $350 to $1,400, depending on the vehicle and root cause.
Which vehicles are affected by B104A?
Au7o has documented B104A across 1 vehicle models from 1 manufacturers: Jeep.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.