VIOFO A139 PRO 4K Dash Cam In-Depth Review
Our verdict on camera coverage, recording modes and parking power
Our take: a strong front camera with a choice of coverage
We like the A139 PRO for a driver who wants 4K UHD front recording and the option to add rear and cabin views without a screen on the windshield. The three-camera configuration is especially useful when what happens inside the vehicle matters as much as the road ahead.
The front uses Sony STARVIS 2; the rear and cabin cameras use the earlier STARVIS generation and record in 1080P FHD. That distinction matters when comparing footage. Full-height front recording also falls from 30 FPS to 24 FPS when all three cameras are connected.
The original range included front-only, front-and-rear and three-camera A139 PRO systems. Choose by the views you need, then check the exact listing’s condition, accessories and availability.
What comes with the camera?
VIOFO’s A139 PRO manual lists the front unit, GPS mounting base, car charger, Type-C data cable, front CPL filter, spare mounting adhesive, static stickers and trim tool as standard items. The rear camera, infrared cabin camera and their connecting leads depend on the configuration.
A memory card, hardwire kit and Bluetooth remote appear separately in the manual. Check the actual package before ordering, especially for a refurbished camera. We would confirm the camera channels, card and parking-power connection together so you can finish the installation without a missing part.
Design, controls and everyday use
The adjustable front lens helps accommodate different windshield angles. Aim it while parked using live view, and do not force it through a complete turn. Pointing the front lens into the cabin takes it away from the road; the separate cabin camera records both views at once.
The front unit has status lights for recording, microphone, GPS and Wi-Fi, plus physical controls for power, recording, file protection, audio and Wi-Fi. Voice notifications tell you the camera’s status. Voice notification is not voice-command control.
The protection button locks the current clip against ordinary loop recording. Download important footage as soon as it is safe; a locked clip is still on the same card and can be lost to formatting or card failure.
The front CPL filter helps reduce reflections. Our CPL filter range can help identify the correct filter for a specific camera. If comparing the earlier T130 or A229 Duo, check their own specifications rather than assuming the cameras and cables are A139 PRO parts.
Video quality: compare the exact channel and mode
The front camera uses an 8MP Sony STARVIS 2 IMX678 sensor, an F1.6 lens and a 140° field of view. The rear and cabin cameras use 2MP Sony STARVIS IMX291 sensors. The Pro’s front-sensor upgrade does not turn all three cameras into STARVIS 2 cameras.
Front HDR helps balance bright and dark areas. We recommend comparing original-quality clips from the mode you plan to use, especially at night. Exposure, motion, glare and distance still affect useful detail; no dash cam promises every license plate.
The infrared cabin camera provides a view in a dark interior. Its IR settings are Off, On and Auto. Active infrared gives black-and-white footage, while Auto lets it respond to the lighting. Check the cabin view with seats and passengers in their normal positions.
| Connected cameras | Front recording | Secondary recording |
|---|---|---|
| Front only | 3840 × 2160 at 30 FPS | None |
| Front and rear | 3840 × 2160 at 30 FPS | Rear: 1920 × 1080 at 30 FPS |
| Front and cabin | 3840 × 2160 at 30 FPS | Cabin: 1920 × 1080 at 30 FPS |
| Front, rear and cabin | 3840 × 2160 at 24 FPS | Both: 1920 × 1080 at 24 FPS |
For three-camera recording at 30 FPS, the manual lists a 3840 × 1600 front mode, which crops the vertical image compared with 3840 × 2160. It also lists a 2K QHD front option. With one or two cameras, the 2K QHD 60 FPS front setting requires HDR to be off. Check the selected mode in the app and confirm it in a saved recording.
Parking recording starts with the power connection
We recommend choosing the parking mode around where you park. Buffered auto-event detection saves detected activity, including footage before the trigger. Time lapse records continuously at a low frame rate without audio. Low bitrate records continuous video with audio in smaller files.
On a busy street, motion detection can produce frequent clips. It cannot know which person or vehicle is important to you. Review a few actual parking recordings and adjust the documented sensitivity and recording timer for your location.
Parking recording needs suitable power after the engine stops. The manual names the HK3-C ACC kit. If considering the HK4, ask us to confirm the exact A139 PRO connection and vehicle fuse taps before buying. A dedicated battery pack also needs the correct output lead and parking-mode signalling.
The manual’s immediate or 90-second entry setting applies to a hardwire cable; it says that delay function does not work with an external battery. Battery condition, cutoff settings, temperature, connected cameras and recording mode affect runtime. We can help plan useful coverage, but cannot promise uninterrupted overnight recording or a fixed number of hours.
Storage, playback and nearby Wi-Fi
The A139 PRO supports cards up to 512GB. VIOFO’s model-specific card guidance says 128GB and 256GB cards can be more stable. Use a suitable endurance card, format it as instructed and check front, rear and cabin recordings after installation.
Connect a nearby phone to the camera’s 2.4GHz or 5GHz Wi-Fi and open the VIOFO app for live view, settings and playback. This is a local connection; Wi-Fi and GPS do not provide cellular tracking or remote parking notifications when you are away.
For longer reviews, power the camera off before removing the card and use a reader or the documented computer connection. Copy the original files before editing or formatting. VIOFO now offers a Windows and Mac player, so the original article’s “no desktop viewer” advice is outdated. Our Dashcam Viewer guide describes another option. GPS display and other metadata features depend on the file and software.
The older non-Pro A139 app artwork is retained for context. Use the A139 PRO’s own settings and instructions. The speed graphic compares example transfers; actual download time depends on the phone, signal and file.
Choose A139 PRO, not A139, on VIOFO’s firmware page. The Pro uses FWA139P.bin. Back up recordings before any required formatting, follow the model’s update instructions and maintain stable power until the update finishes.
Install for a clear view and secure cable routing
Place the front unit where it does not obstruct your view, with the lens looking through a clear area of glass. The static sticker sits between the windshield and adhesive mount to help later removal. Check the angle in the app before securing the cables.
The slim coaxial leads connect the rear and cabin cameras; they are different from the Type-C power lead. Power off before connecting or disconnecting a secondary camera, protect the small connectors and route cables clear of airbags, pedals, controls and moving trim.
The car charger is the straightforward driving-power option. A socket that switches off with the vehicle stops supplying power, so plan parking power separately. If you already own our PowerCell 8, send us its output-cable details so we can confirm the connection rather than assuming any USB lead will enable parking mode.
Questions we would answer before choosing your setup
Will the three-camera system record full-height 4K UHD at 30 FPS?
The manual lists 3840 × 2160 at 24 FPS with all three cameras connected. Its 30 FPS three-camera option uses a 3840 × 1600 front image. Decide which framing and frame rate you prefer, then verify the saved clips.
Can a parking battery keep all three cameras running for days?
Do not choose a pack from a fixed runtime promise. Its usable capacity, output connection, charging opportunities, camera settings and temperature all matter. Tell us how long you park and drive so we can help plan the setup and explain its limits.
Does rotating the front lens replace the cabin camera?
It changes where that camera looks. Turning the front lens into the cabin loses the forward view. Use the separate cabin camera when you need both views recorded at once.
Are locked clips safe from formatting?
No. File protection helps against ordinary loop overwriting. Formatting erases the card. Copy important files to separate storage and confirm they play before changing or formatting the card.
Let us help match the camera and parking setup
The A139 PRO makes the most sense when its camera coverage fits your vehicle and you are comfortable using a phone instead of a screen. For an existing camera, we would start with healthy storage, clear views and a verified power connection before replacing hardware.
Tell our team your vehicle year, make and model, whether you need cabin recording, how long you park and any wiring or battery pack already installed. We can help you choose the right parts and check an original A139 PRO against the current VIOFO range.
