Replaced GPS and can't locate satellites & solid red light on AC

[AlonBerman]

Problem?

• Compass 1 was not working so I replaced the GPS module.
• After replacing the GPS module compass 1 sensor was working
• The GPS however is not working now.
  • There is a solid red light on the back of the AC
  • The RC says SYS WARNING > CHECK APP
  • The app says "Navigation system error. Check redundancy state"
  • No satellites are found (shows greyed out on the app)
  • I can not fire up the motors.

Was unit in a crash?

• Yes
• Replaced left rear arm, mid shell, top shell

What have you tried so far?

• I tried 3 band new modules and they all behaved the same
• If I put the old module in it picks up satellites again and I can fire up the motors
• I tried to refresh the firmware
• I downgraded the AC & RC firmware and then upgraded to various versions
• I left the AC outdoors to try pickup satellites for about 15 minutes

What device are you using ( iphone , ipad, Samsung , etc)?

• Samsung S7 Edge & S9+

What firmware are you running ( aircraft, remote controller)?

• AC: V01.04.050 (Official)
• RC: V01.04.050 (Official)

What Go app version are you using?

• 4.3.2

Any modification? (if so what)

• None

Did you change anything or install any apps?

• No

Do you have a video or pictures of the problem?

• https://www.dropbox.com/s/qevvypi3oun5fii/DJI%20Mavic%20error%20on%20Compass.mp4?dl=

Original compass error



Original Compass Sensor



Error with new GPS - no satelites


New GPS error on app




New GPS Compass 1 now picking up (after a calibration it works correctly)

 

[kidroc]

Why replace the gps if your compass was the problem? replace one or both of the compasses

 

[Tesadorn]

Interesting, is there ANYWAY to test these GPS modules in a known good bird? Where did you get them? Were they in original DJI packaging or generic? Believe it or not after seeing that your old GPS still works minus the compass I would suspect all three of the new ones.. this is very strange indeed

 

[AlonBerman]

Interesting, is there ANYWAY to test these GPS modules in a known good bird? Where did you get them? Were they in original DJI packaging or generic? Believe it or not after seeing that your old GPS still works minus the compass I would suspect all three of the new ones.. this is very strange indeed

I believe they were original. All were in Dji packaging with serials etc. I will try find someone who is willing to let me open theirs to try it - great idea!

 

[AlonBerman]

Why replace the gps if your compass was the problem? replace one or both of the compasses

Compass 1 & the GPS are a single unit that sit at the back of the drone (in the top shell).

I am going to open the remove the glue on the join - perhaps compass 1 is just a lose wire and a little solder will fix that.

 

[kidroc]

Compass 1 & the GPS are a single unit that sit at the back of the drone (in the top shell).

I am going to open the remove the glue on the join - perhaps compass 1 is just a lose wire and a little solder will fix that.

gotta thank you all for the education.. I did not know that..

 

[AlonBerman]

I have not come right with the new GPS module but thought I would take a closer look at the original module. I carefully removed the white glue on the first solder point and saw the white cable was broken. A quick solder and it solved the original Compass 1 not found error.

The store said they will take the module back.

 

[AlonBerman]

Update on this... GPS module was apparently for a platinum and not the Mavic Pro.

 

[Tesadorn]

Really weird.... I have swapped a few plat to pro GPS units and never had a problem at all.... The only think I know for sure that is diff is the ESC board.....

 

[Rockowe]

I remember - that the GPS had a Problem with the NEW Updates-
May I suggest that You Roll back the FIRMWARE - (but don't load New) … and in that Mode - Retest …

try

What firmware are you running ( aircraft, remote controller)?

• AC: V01.03.000 (Official)
• RC: V01.03.000 (Official)

 

[FoxhallGH]

May be a stupid question, but I've not seen any mention of you doing a Compass calibration dance???? Any chance it just needs a calibrate ?

 

[Diederik]

Keep in mind that when fitting a new Gps the light will stay solid red for around 20 minutes as it downloads information to determine where it is in the world. This is common with all new gps units as they have not been powered up and still need all the required satellite information

In a new craft they get activated inside the aircraft at the factory but the new Part ones do not and you have to just wait the 29 minutes or so. This was very common years ago with old APM systems etc.

 

[Tesadorn]

Keep in mind that when fitting a new Gps the light will stay solid red for around 20 minutes as it downloads information to determine where it is in the world. This is common with all new gps units as they have not been powered up and still need all the required satellite information

In a new craft they get activated inside the aircraft at the factory but the new Part ones do not and you have to just wait the 29 minutes or so. This was very common years ago with old APM systems etc.

This is simply NOT true anymore... The GPS should acquire max sats within few minutes

 

[Diederik]

As a matter of facts it is true. i bought two thinking one was faulty, a respected gentleman here advised me and reminded me of this, I left it outside for 20 minutes, red changed to green and I was ready to fly. From there on the gps worked as normal

 

[AlonBerman]

As a matter of facts it is true. i bought two thinking one was faulty, a respected gentleman here advised me and reminded me of this, I left it outside for 20 minutes, red changed to green and I was ready to fly. From there on the gps worked as normal

Thanks for the feedback - I wish I was told this when I bought the new board. I'll let the store K ow. Hopefully my repair holds up but if not - I will wait for 30 mins and see.

I wish the RC said "New GPS detected. Please wait for up to 30 mins whilst it calibrates" and not "System error. GFY"

 

[AlonBerman]

May be a stupid question, but I've not seen any mention of you doing a Compass calibration dance???? Any chance it just needs a calibrate ?

I did the dance but knew it wasn't the issue as the poor compass signal is still picking something up. This was dead hence I wanted to replace it.

 

[kidroc]

As a matter of facts it is true. i bought two thinking one was faulty, a respected gentleman here advised me and reminded me of this, I left it outside for 20 minutes, red changed to green and I was ready to fly. From there on the gps worked as normal

yes it is..