Causes
- A failed or half-installed 4G module firmware update — the most commonly reported trigger: the 70mai app pushes a 4G module firmware update, the camera shows a progress bar and restarts, and from then on the module shows "4G offline" in the app with a permanently blinking red LED. Owners describe the module working perfectly for weeks or months, then going permanently offline right after accepting the module update — one user's suggested update "bricked" the module until they cycled power.
- SIM card issues: PIN lock, voice-only plans, or unsupported carriers — the module will not register with the network if the SIM has a PIN enabled, if the plan is voice-only, or if the carrier is not supported. Owners report the module rejecting a Virgin SIM with a continuous red flash, and note the US 4G module effectively requires an AT&T data SIM for reliable operation. A SIM PIN left enabled is a frequent hidden cause of the red LED.
- Heat-deformed SIM holder or loose SIM contacts — the 4G module sits on the dashboard and absorbs cabin heat, which can soften the plastic SIM holder and lose contact with the card. One owner fixed a months-long red-LED problem by bending the SIM slightly so it seated more firmly in the holder — the module connected immediately after. Loose contacts from heat or vibration reproduce the same "no carrier" red flash.
- Account or app migration breaks the module binding — owners forced to migrate to a new regional 70mai app (e.g., the EU app) must re-add the 4G module, and the binding step fails with an error even though the module LED is a solid, non-flashing green. A solid green LED with "4G offline" in the app points to a binding/account problem rather than a radio problem.
- Wrong APN settings or network mode — the module needs the correct APN for your carrier, and in some regions it only registers on 3G networks. Owners with an unlimited Verizon SIM saw "poor carrier signal" on every live view attempt, and another user fixed the connection by switching the network mode from 4G to 3G. Incorrect APN entries make the module flash red and refuse to connect.
How to Fix
- Power-cycle the whole system — unplug the camera from its 12V supply and plug it back in (if hardwired, pull the fuse or disconnect the harness for 10 seconds). One owner fixed a recurring red-LED offline problem five separate times this way: "I needed to unplug camera from 12v, plug again and it is working." This is the first thing to try after any module update.
- Read the module LED to narrow the fault — a solid green LED means the module is powered and registered; a blinking red LED means it cannot register with the carrier. If the LED is solid green but the app says "4G offline," the problem is the app binding or account, not the radio — skip to the re-binding step below.
- Remove the SIM, disable the PIN, and reseat it firmly — power the module off, eject the SIM, and confirm there is no SIM PIN enabled (put the card in a phone and clear the PIN if needed). Reinsert it until it clicks, and make sure it is a data-enabled plan on a supported carrier — owners report the US module works reliably with AT&T data SIMs, and that some carrier SIMs are simply rejected. One owner solved it by bending the SIM ever so slightly to improve contact with the holder, but reseating cleanly usually suffices.
- Re-enter the APN and check the network mode — in the 70mai app, open the 4G module settings and verify the APN matches your carrier's data APN. If the module registers on 3G but not 4G (or vice versa), switch the network mode in the module settings — one owner's module started working immediately after switching from 4G to 3G. Confirm with your carrier that the plan allows data and has no extra internet lock.
- Re-bind the module in the app — if you migrated accounts or apps, remove the 4G module from the device list, put the module back into pairing/binding mode, and re-add it. With a solid green LED and an app-side error, this re-binding step resolves the "add failed" loop owners hit after moving to a new regional app.
- Retry the module firmware update from a clean state — if a module update is pending and the button appears to do nothing, restart the app, power-cycle the camera, and try again. Owners who went through this found the update eventually pushes after the module has been power-cycled; if the module firmware version is lower than required and the update will not take, note it for support.
- Verify carrier coverage where the car is parked — a blinking red LED in a garage or underground lot can simply mean no signal. Move the car to an area with confirmed coverage and wait a few minutes for the module to re-register before assuming a hardware fault.
- Contact 70mai support if it still will not register — if the LED keeps blinking red after power cycles, SIM reseating, APN checks, and a coverage test, the module likely has a fault (owners report modules dying right after a suggested update and needing warranty replacement). Contact 70mai support with your order number, the module's behavior, and the error screenshot from the app — be persistent, as multiple owners had to push for a replacement module rather than endless error-log requests.