Symptoms of a dead/ dying battery?

[murcod]

I was wondering if a dead/ dying battery could cause the loss of most of the last clip. I'm sometimes only getting a very small portion of the last file - it almost appears as though it is the final second or two as the Mobius is shutting down. The remaining minutes of the final (up to 5 minute) clip are missing.

The Mobius in question doesn't get a lot of use and can sit 2 weeks (or longer) without the vehicle being driven. (I just did a quick test and the battery only lasted 4 minutes on it's own steam.... I'll try charging it on a wall charger for a couple of hours with the Mobius off/ not recording and do it again.)

I first noticed it today after trying to view footage from when the vehicle was in getting serviced - so I'm not sure what was going on with the IGN. However, checking back through footage over the last couple of drives there are intermittent "full" files followed by a time gap and then a short ~2210kb file? It appears to always only happen with the last file.

I recently updated to V1.20 but I think this issue predates that update. It's a 32Gb Sandisk Class 10 card that has previously worked perfectly (it's near full so would be over writing files....)

 

[murcod]

Oh, I forgot to mention I'm not losing the time / date at all - that is clocking over fine and not being reset.

 

[Isoprop]

Oh, I forgot to mention I'm not losing the time / date at all - that is clocking over fine and not being reset.

If your battery can only record about 4 minutes when fully charged then it will almost certainly render your camera unreliable. I recently had some very strange results while testing the Mobius with a 'puffed' battery. When I replaced the battery things were back to normal. If the battery is completely dead the PC will most likely not even recognize your camera.
BUT, your problem is most likely due to a corrupted FAT (File Allocation Table). Try in-camera formatting your card.

 

[murcod]

Thanks I'll give that a go.

One other thing I've noticed - a lack of a green charging LED. If I plug it in to a "wall charger" it will flash green once, then auto start and flash orange - green for a few seconds; but then just flash orange. If I turn the Mobius "off" (ie. turn it off after the auto start) and leave it on charge there is no green LED to indicate charging -> shouldn't there be? Or does the Mobius need to be operating to charge- I had a look at an old version of the user manual and it didn't say if that was the case or not?

I just tried it again and only got a minute or two run time after a couple of hours charging in the "off" state. I'm leaning towards the battery or charging circuit? The corrupt files (on rechecking the card contents) always seems to be the last file before shutdown, with only a small 1-2 second "grab" of the very end of that file as the camera is shutting down.

It makes sense with the files I got from car being serviced. There are a lot of the small ~2000kb files that would match up with them running the engine for under 5 minutes and the recorded file being just the last couple of seconds.

 

[Isoprop]

In Windows explorer you can set the window to always show the length of your videos. When your files are shown, click View->Choose details... and put a click in the 'Length' check-box. VERY useful!!

You are absolutely right. Your charging IC on the mainboard could be defective. This has known to happen, albeit very rarely. Since you're not from the RC crowd I doubt you'll have a LiPo battery charger. If you do, you could try charging your 1S battery with it. Otherwise, your only alternative is to first put in a new battery and see if the green charging LED functions correctly. If you have an old 808 (#11, #16, #18 etc.) with a good battery you can use that in place of the Mobius battery, but only for testing purposes. First double-check the battery polarity!

If any of the other LEDs are lit, it's all but impossible to see the green LED unless you take off the case. The camera should be OFF when you charge the battery. If the battery is charging, the green LED will (should) be lit.

 

[murcod]

I did some more experimenting. While my battery isn't in top condition (probably far from it!) I have had some interesting results.

I can get it to fail using a wall charger and disconnecting the USB connector to simulate the power being turned off. The top LED will give one blue flash followed by a red flash when the failure occurs - that happens immediately at power disconnection with it set to 10 second power off delay. Now, I don't think it's the battery because I can immediately (with no external power) start the Mobius up and record video for 30-60 secs and power it down - with the 10 second delay working perfectly. I did that twice after a power disconnect failure; so to me, that would tend to rule out the battery (unless it's somehow intermittent?)

I've just reformatted the card and will try it some more.

 

[murcod]

The camera should be OFF when you charge the battery. If the battery is charging, the green LED will (should) be lit.

Interesting. I might need to dissect some of my other Mobius and do some comparsions. The green LED did come on once last night with the wall charger and Mobius off, but didn't stay lit for long.

 

[murcod]

Okay, I've grabbed the Mobius out the wife's car (the one that has spent it's entire life in the vehicle through the Aussie Summer) and it's behaving very differently. Plugged into the PC the green light is staying on indicating charging - the other one would only do that for a short time period (10-15sec) .... if at all.

All the video files are perfect as well. (Ironic again as it's the one with the 64Gb card formatted to FAT32!)

The vehicle it's fitted in gets driven most days.

 

[murcod]

Okay. Formatting the card (in camera) made no difference.

I swapped the case tops (with batteries) between the two cameras and the failing Mobius is now charging correctly and saving the last file (repeatedly without any problems.)

The previously working Mobius initially looked like it too was working , however it has now begun failing. The charge light isn't staying on long and the same light sequence is occurring when the 10 second delay is failing.

So, the battery is definitely looking like the cause. (The battery that was protected from the Aussie Summer heat!!!)

I'll pull out the third Mobius and see how that is fairing. It's fitted as a rear camera in the same car that had the failure.

 

[GJHS]

Reading the Mobius RC Forum a while back, it seems a few people were having problems with their cameras after letting them sit for long periods of time. So I'm guessing cycling those small batteries is a key to longevity.

 

[murcod]

Yes, possibly more so than the heat everyone is so paranoid about. It's certainly been the case for me!

The vehicle would have been sitting for about 2 weeks at a time and then driven for around an hour before sitting again for another two weeks. Out of interest, the rear camera appears okay- it did miss one clip but that could have been because the ignition was cycled while it was in the 10 second shut down period? I've change them all to shut down immediately, which will hopefully alleviate that happening.