Causes
- The rear plug is not fully seated the rear camera connector pushes into the port on the A810 with no locking latch, and insertion depth is shallow. Vibration and the weight of an unsupported cable walk the plug back out over weeks, which drops the rear channel or makes it appear and disappear between clips.
- The cable is crushed or flexed at the tailgate grommet routing through the rubber boot means the cable bends every time the hatch opens. A pinched conductor breaks the video pair while the power pair still passes, so the front camera keeps recording normally and only the rear channel goes missing.
- The wrong rear camera or cable is fitted the A810 is built for the RC11 and RC12 rear cameras. Cables and cameras from older 70mai kits, and generic four pin rear cameras, have different pinouts and are not detected even though the plug physically fits.
- The rear channel was switched off or reset after a factory reset or firmware update the camera can come back in single channel mode with the rear icon missing from the home screen. Nothing is broken, the second channel is simply disabled.
- The rear unit has water damage or took an impact the rear camera lives on the inside of the rear glass, where condensation and a failed housing seal can reach the board. A shorted rear unit draws no current, and the front camera reports nothing connected rather than a fault.
How to Fix
- Check the home screen first. Power the camera and look for the rear channel thumbnail or the rear icon. If it is absent, open Settings and confirm the rear camera option is enabled, then restart the camera and look again.
- Reseat both ends with the power off. Unplug the cable at the A810 and at the rear camera, inspect the plugs for bent pins or corrosion, and push each one in until there is no visible gap. Start the car and check the rear channel in the app's live view.
- Do a wiggle test at the grommet. With the app in live view, flex the cable gently where it passes through the tailgate boot and at both plugs. If the rear image cuts in and out, the break is in the cable and replacing it is cheaper than chasing the camera.
- Bench test with the short cable. Plug the rear camera into the front unit with the short cable from the box, right next to each other. If it is detected there, the installed cable or its routing is the fault; if it still is not detected, move on to the camera and settings.
- Reset and re-enable the rear channel. Open Settings, run the factory reset, then turn the rear camera option back on and set the rear resolution again. A reset clears a stuck channel configuration that survives a plain reboot.
- Update the firmware with the rear camera connected. Join the camera's Wi-Fi, open the 70mai app, and install the pending firmware with both cameras plugged in. The update detects the attached rear unit during the flash, and dual channel fixes have shipped in firmware releases.
- Confirm the hardware matches the A810. Check the label on the rear camera. RC11 and RC12 are the supported units, and a camera pulled from an older 70mai kit will never be recognised no matter how the cable is seated.
- Reroute the replacement cable with slack. When fitting a new cable, leave a service loop of 10 to 15cm inside the tailgate and tape the cable so the flex happens on a straight run, not at the plug or the grommet edge.
- Claim warranty if a known good rear camera is not seen. A rear camera that fails the short cable bench test on a reset, updated A810 is faulty. Contact 70mai support with the serial number, the order details, and a photo of the empty rear channel on the home screen.
