70mai A900: problems, parts and running costs

Checked: 2026-10-17

Summary

The A900 is a compact dual-4K dash cam (front and rear 3840×2160 at 30 fps) with a supercapacitor, Wi-Fi 6 and buffered emergency recording of up to 190 seconds before an impact. Its usual gotchas are what is not in the box: 4G remote features wait on an OTA and a separately sold kit, parking mode needs its own hardwire kit, and the unnamed sensor is not the Sony unit the A900 Ultra shares the name with. Running costs are a microSD card plus optional hardwire kits and possibly a 4G subscription.

Common problems and fixes

4G remote features are not live yet — the hardware supports 4G Cloud+ 2.0, but 70mai says the full service features arrive through a later OTA update; remote album, cloud backup, hotspot and two-way voice need the separately sold 4G Hardwire Kit 2 (UP11), and some need a paid 4G Cloud+ subscription, with two-way voice behind the Premium Plus plan. Fix: wait for the OTA and budget for the kit. [1][4]
Parking mode needs a separately sold hardwire kit — 24-hour surveillance and 1 fps time-lapse only work with the 70mai Hardwire Kit; budget for it and possibly professional installation. [1][4]
It is not the Sony-sensor camera — 70mai’s own A900/A900 Ultra comparison marks Sony CMOS as present on the Ultra and absent on the A900, whose product page names no sensor; anyone buying the Ultra’s sensor story is buying the wrong box. [3][1]
Warranty depends on where you buy — the US and UK official stores list 12 months and the EU store lists 24 months; a third-party listing claimed 18 months, which conflicts with the US store policy. [5][6][7][10]
Card handling — the manual says to format the microSD card and not to insert or remove it while the unit is on. [2]

Parts and consumables

Yearly running cost

Not enough data. No recurring figures were reported in the checked sources. [4][1]

When it is a good buy

AliExpress listed the front-only A900 at US$97.49, the front-and-rear set at US$123.49 and the set with an UP03 hardwire kit at US$139.49 (OzBargain, Aug 2026); a 70mai autumn promotion listed the 4K dual set with 4G remote and a 64 GB card at $159.99 against a $199.99 reference (Dealmoon, 2026); a price-history tracker records the front-and-rear set at an ordinary $199.99 with a recorded low of $149.99 (BasketPrice, Oct 2026). At or below $100 it is strong value for a compact dual-4K unit; $101–$130 is reasonable for the front-and-rear set; $131–$160 is fair once the hardwire kits and any subscription are added; at the common $199.99 it is weak-to-fair, because the better-specified A900 Ultra sits in the same series for similar money. [8][9][10]

When the Sony STARVIS 2 IMX678 sensors, LVDS rear transmission or the low-power parking mode of the A900 Ultra matter, the Ultra is the better choice; the standard A900 is the better pick when compact dual 4K, a supercapacitor and Wi-Fi 6 are the priority. [3][4]