P4 won't go faster than 4 mph with collision system on

[DonWiley]

I'm seeing a strange problem with my P4 CNE. If the collision avoidance system is turned on it will only go about 4 MPH in the forward direction. If I turn off the collision avoidance, switch to sport mode, fly backwards, or sideway I can get it to 30+mph without a problem.
I don't get any bars or notifications on Go4 from the collision avoidance indicating something present in front of the aircraft.

I'm also tried some of the advance flight modes - in course or home lock as long as the aircraft is flying anything other than forward it fly fine and speed is good, the close it gets to flying forward it slows down again.

I've rolled back and reloaded the firmware in the bird, done IMU and compass cals, tried it with the remotes for my P4P and P4P+ and always the same results.

Has anyone seen this before and any ideas on how to fix this?

Thanks,

 

[WV. Rootman]

Check to make sure the sensors are clean with nothing obstructing them. Try calibrating the sensors.

 

[Phil Crossley]

as noted above, when I had a similar issue, it was because I had a gimball protector on that was blocking the downward vision sensors (so it thought it was very close to the ground all the time)

 

[DonWiley]

Check to make sure the sensors are clean with nothing obstructing them. Try calibrating the sensors.

Calibrating the sensors was the first thing I did when I notice the problem, didn't make a difference. Nothing blocking any of the sensors either.

 

[DonWiley]

as noted above, when I had a similar issue, it was because I had a gimball protector on that was blocking the downward vision sensors (so it thought it was very close to the ground all the time)

I know this one all too well, I had the same issue with one of my P4Ps when I put a gimbal protector on it. Didn't realize I had a problem until I tried to land. Held the left stick down and assumed it would slow as it usually did and then do a nice gentile landing, NOT, it came down at full speed and never slowed, it hit the ground square and bounced up again about 5 feet, both sets of legs were a little bent and the screw covers for the legs blew out. I go lucky, no significant damage. I have the gimbal protector in a box someplace safe and away from the drone, good idea, bad implementation and results.

 

[ron-ep]

I'm seeing a strange problem with my P4 CNE. If the collision avoidance system is turned on it will only go about 4 MPH in the forward direction. If I turn off the collision avoidance, switch to sport mode, fly backwards, or sideway I can get it to 30+mph without a problem.
I don't get any bars or notifications on Go4 from the collision avoidance indicating something present in front of the aircraft.

I'm also tried some of the advance flight modes - in course or home lock as long as the aircraft is flying anything other than forward it fly fine and speed is good, the close it gets to flying forward it slows down again.

I've rolled back and reloaded the firmware in the bird, done IMU and compass cals, tried it with the remotes for my P4P and P4P+ and always the same results.

Has anyone seen this before and any ideas on how to fix this?

Thanks,

Had this same issue. Was going to say to go back to previous software version as this fixed my issue. Seems you already did that. Sorry to say I don't have any more recommendations beyond that.

I'll attach my original post about it below. Good luck.

Just a thought and solution about the Phantom 4 in 2020

Hey everyone I just wanted to put something out there for anyone that may benefit from this. I had been struggling with my P4 flying extremely slow. Specifically in the forward direction. We're talking 5 or 6mph. At times it would suddenly speed up to about 9mph but that wouldnt last long at...

phantompilots.com

 

[lannes]

Calibrating the sensors was the first thing I did when I notice the problem, didn't make a difference. Nothing blocking any of the sensors either.

Did you re-calibrate the sensors using DJI Assistant 2 on the PC ?

 

[Bone4Drone]

Calibrating the sensors was the first thing I did when I notice the problem, didn't make a difference. Nothing blocking any of the sensors either.

I understand you calibrated them but did you clean the sensors? I had that problem and nothing helped until I cleaned them. They do pick up a lot of trash. Clean 'em all as long as you're at it.

 

[Bone4Drone]

I know this one all too well, I had the same issue with one of my P4Ps when I put a gimbal protector on it. Didn't realize I had a problem until I tried to land. Held the left stick down and assumed it would slow as it usually did and then do a nice gentile landing, NOT, it came down at full speed and never slowed, it hit the ground square and bounced up again about 5 feet, both sets of legs were a little bent and the screw covers for the legs blew out. I go lucky, no significant damage. I have the gimbal protector in a box someplace safe and away from the drone, good idea, bad implementation and results.

Ditto. I held the stick down and my P4P dropped like a lead bowling ball. Started hearing a strange knocking sound. Turned out to be my knees. Let go of the stick just in time to save my gimbal from turning into a periscope.

 

[DonWiley]

Did you re-calibrate the sensors using DJI Assistant 2 on the PC ?

Yes, that was the first thing I tried. I rolled the firmware version back yesterday and, weather permitting, I will test fly it today with the pervious firmware version.

 

[DonWiley]

I understand you calibrated them but did you clean the sensors? I had that problem and nothing helped until I cleaned them. They do pick up a lot of trash. Clean 'em all as long as you're at it.

Yes, everything was cleaned and checked.
It has been doing this since it's very first flight 2 months ago. This is the P4 Chinese New Year Edition I purchased in June from a German company DJI P4 in RED, it's still new and under warranty, I'm trying to make sure I haven't missed something before sending it back to DJI.

 

[Deleted member 62848]

Yes, everything was cleaned and checked.
It has been doing this since it's very first flight 2 months ago. This is the P4 Chinese New Year Edition I purchased in June from a German company DJI P4 in RED, it's still new and under warranty, I'm trying to make sure I haven't missed something before sending it back to DJI.

Seems there might be obstacle avoidance issue,what's it like in pgps mode without sport mode and OA off,,try simple reinstall off app,,try imu calibration aswell

 

[DonWiley]

I rolled back the firmware to the previous version and did several test flights, everything worked great, no problems, 30+ PPH in all directions. Will now try to reload the current firmware and see what happens.

 

[DodgeTheTree]

I'm seeing a strange problem with my P4 CNE. If the collision avoidance system is turned on it will only go about 4 MPH in the forward direction. If I turn off the collision avoidance, switch to sport mode, fly backwards, or sideway I can get it to 30+mph without a problem.
I don't get any bars or notifications on Go4 from the collision avoidance indicating something present in front of the aircraft.

I'm also tried some of the advance flight modes - in course or home lock as long as the aircraft is flying anything other than forward it fly fine and speed is good, the close it gets to flying forward it slows down again.

I've rolled back and reloaded the firmware in the bird, done IMU and compass cals, tried it with the remotes for my P4P and P4P+ and always the same results.

Has anyone seen this before and any ideas on how to fix this?

Thanks,

Like others have stated. Try cleaning the sensors. Same thing happened to me.

 

[uberamd]

I had this exact issue in the latest firmware with my “new” (purchased 2016, never used until this week) Phantom 4.

Forward movement was a crawl. Backwards movement was normal. No amount of cleaning would fix it, as it was literally just removed from the factory box and updated. Rolling back fixed it immediately.