I have experienced this downward sensor error on my 4 month old Mavic Platinum.  I have checked my sensors for gunk in them.  Nothing there but I cleaned them off any way. I have upgraded the firmware, rebooted the Mavic, recalibrated compass and IMU  I tried to recalibrate the sensors via DJI Assistant but that doesn't function at all.  Any help or advice would be appreciated.

Hi there, I'm sorry to hear about the issue that you are experiencing. May I know that did your drone crash before or not? At the same time, could you please show us a screenshot of the error message on DJI GO4 app, we'll look into it. Thanks!

DJI Diana Posted at 2018-4-9 17:54
Hi there, I'm sorry to hear about the issue that you are experiencing. May I know that did your drone crash before or not? At the same time, could you please show us a screenshot of the error message on DJI GO4 app, we'll look into it. Thanks!

No crash, message just appeared in mid flight.  

Good news though, after researching several forums i found the issue.  I had to uninstall DJI Assistant, restart my Win10 laptop choosing the option of accepting unsigned device drivers.  I then reinstalled DJI Assistant accepting the Win10 warnings for three DJI unsigned device drivers.  After this I launched DJI Assistant and was able to recalibrate the forward and downward sensors successfully..

MFPullen Posted at 2018-4-9 18:00
No crash, message just appeared in mid flight.  

Good news though, after researching several forums i found the issue.  I had to uninstall DJI Assistant, restart my Win10 laptop choosing the option of accepting unsigned device drivers.  I then reinstalled DJI Assistant accepting the Win10 warnings for three DJI unsigned device drivers.  After this I launched DJI Assistant and was able to recalibrate the forward and downward sensors successfully..

That's really a good news, I'm glad to know that you have solved the issue and everything turns out to be great. Please fly outside and check the performance, if there is any further issue, please feel free to let us know, we'll here for help.

DJI Diana Posted at 2018-4-9 22:20
That's really a good news, I'm glad to know that you have solved the issue and everything turns out to be great. Please fly outside and check the performance, if there is any further issue, please feel free to let us know, we'll here for help.

Hi Diana.
I have the same situation with my Mavic Pro 4 months old. I tryed reinstall all drivers and recalibrate, but it did not fix the issue.
I sent the drone to assistance in Brazil, but it returned with the same problem.
They said they replaced the sensors, but the issue persists.
Could you help me to the next steps?
Thanks

Here is the image of error:

Guina Posted at 2018-4-16 18:12
Here is the image of error:

[view_image]

I will be interested to see if you get any help with this one. A few of us with Phantom 4 Pros have exactly the same error message and it seems to occur on every flight resulting in the rear lights going solid red and the landings are heavier than normal. The error never shows up in the log files.Can you tell me what firmware version the Mavic has and what version of the GO 4 app you are using.

Jenee 2 Posted at 2018-4-16 20:28
I will be interested to see if you get any help with this one. A few of us with Phantom 4 Pros have exactly the same error message and it seems to occur on every flight resulting in the rear lights going solid red and the landings are heavier than normal. The error never shows up in the log files.Can you tell me what firmware version the Mavic has and what version of the GO 4 app you are using.

Hi Jenee,
I´m using a GO 4 version (v4.2.12) and aircraft firmware version V01.04.0300.
I sent the equipment to local authorized service and they said they changed the sensors, but the error persists.

Guina Posted at 2018-4-17 05:16
Hi Jenee,
I´m using a GO 4 version (v4.2.12) and aircraft firmware version V01.04.0300.
I sent the equipment to local authorized service and they said they changed the sensors, but the error persists.

Thanks for that. I just wanted to check if you were on the latest GO 4 app and firmware and you are. I am not sure what the issue is but I think there may have been some change in the code or additional code in either the latest firmware versions or the Go 4 app that is now detecting an error somewhere. If I am able to find out anything, I will let you know.

Jenee 2 Posted at 2018-4-17 19:59
Thanks for that. I just wanted to check if you were on the latest GO 4 app and firmware and you are. I am not sure what the issue is but I think there may have been some change in the code or additional code in either the latest firmware versions or the Go 4 app that is now detecting an error somewhere. If I am able to find out anything, I will let you know.

Okay! Thank you!

I have a Phantom 4 and I started getting the exact same error. Not very old and never been crashed.  I have done all of the calibrations.  It seemed to happen after a firmware update.

I have this problem as well.   I went to fly my 'backup' MP1 yesterday for the first time in about a year.   It was fine the last time I flew it, but now I'm getting 'Downward Sensor Errors' mid flight - both yesterday and today.   It sends the back end indicator light solid red.   I tried rebooting everything between flights but it didn't make a difference.   It happened on two flights yesterday, and two tonight.   There were some shorter, lower altitude hovering only flights in between just to see what would happen and I didn't get errors.   They seem to only happen when I go above the downward sensor active height.

Since I haven't flown this particular Mavic in a very long time, I decided to restore it to factory defaults, refresh the firmware (same version it had), removed the app from my phone, deleted all the DJI directories and reset it up from scratch. I also recalibrated all the sensors, IMU and gimbal. I didn't bother with the compass since it showed very little interference prior to takeoff. Same error. Two flights..

I uploaded the log from one of the flights with the error to PhantomHelp - and sure enough, at 174 ft, suddenly the VPS indicator goes from NA to .7ft and the error is thrown and it goes back to NA.   Then the VPS starts reading again as I get within the VPS effective distance.   Could my Polarpro landing gear extensions be causing some light reflection issues?
LP

DJI Diana Posted at 2018-4-9 17:54
Hi there, I'm sorry to hear about the issue that you are experiencing. May I know that did your drone crash before or not? At the same time, could you please show us a screenshot of the error message on DJI GO4 app, we'll look into it. Thanks!

My drone landed by itself after I selected return to home - every time I have used it previously it has had no issue. Despite the home point being updated the drone did not return. It stayed in the same place until the battery eventually died and it landed itself in water. I have dji after care (still valid) and DJI is refusing to honour it. Can someone please help..

Jenee 2 Posted at 2018-4-16 20:28
I will be interested to see if you get any help with this one. A few of us with Phantom 4 Pros have exactly the same error message and it seems to occur on every flight resulting in the rear lights going solid red and the landings are heavier than normal. The error never shows up in the log files.Can you tell me what firmware version the Mavic has and what version of the GO 4 app you are using.

I have a Phantom 4 and I’m experiencing the error and problems. Were you able to find a solution?

I have downward sensor issues with a Mavic Pro 2 after 6 months (DJI have already charged me £300 for the dreaded gimbal motor load issue - can't believe they charge you while drone is under warranty and never crashed). Anyway, does anyone know how to fix the downward sensor issue? I had fixed it by downgrading to the last firmware but the drone has since auto upgraded and won't let me downgrade now. Cant believe DJI release firmware which prevent me using my drone then they want to charge you money to fix the issue......criminals.

DJI Diana Posted at 2018-4-9 17:54
Hi there, I'm sorry to hear about the issue that you are experiencing. May I know that did your drone crash before or not? At the same time, could you please show us a screenshot of the error message on DJI GO4 app, we'll look into it. Thanks!

Im having the same issue with mine crashed  my old drone sent it off for repair and was told to pay €460 for the repair
I bite the bullet and paid for repair and when i got the drone back from the first flight and every second flight after that im getting the downward sensor messages have downgraded firmware and re-calibrated sensors via dji assist app  but still mothing sent it back to dji and i have been told they replaced my crashed drone with another drone they had in factory in Netherlands without saying a word so a three week old previously owned drone has had nothing but issues with dji charged me for a repair that was never carried out and just gave me someone elses problem drone
So after buying my drone in April i have now spent €2000 on drone and repair that they never did and yet im still without any drone
Gangsters folks it is a joke avoid DJI at all costs folks  

Drone telling me its landing as it has descended to 1.6ft when actually you can see from photo it is actually hoovering at 39ft and second image is the error message that i keep getting now on a three week old replacement drone that i never wanted to begin with