RTC Battery Type - A139 Pro - 01-01-2000 Recording Failure

[Michelin Man]

Does anyone know the RTC Battery type that is in the A139 Pro? I thought I'd ask first before taking the camera apart and so I can order it.

I assume I have a faulty RTC battery. I don't drive my car as much as I used to (used to be daily, then a couple times a month, now a couple times a week). After checking memory card and noticing the dashcam had not been recording. (no error, voice says recording, even beeps when "locking" video, but no file. At most one file)

I then noticed the date was stuck at 01/01/2000. After formatting card and syncing time with phone. All seemed to be good for a while (since Jan). (was even working fine last week) Had also updated to FW V1.2 since Jan. Went to check the camera again today and its doing the 01-01-2000 date file thing again.

 

[JardaB]

As far as I know, the camera does not contain a backup battery or accumulator, but a capacitor.

If the date and time do not match, the cause is more likely to be the GPS. Is there a problem with the GPS module connection in the base under the camera? The time should be set after connecting the GPS.

The time can be set once in the setup from a mobile phone.

 

[Michelin Man]

So I decided to open it up.

For anyone else who may be searching this up. The battery is a MS621FE its a rechargeable lithium manganese silicon battery. 3v, 5.5mAH. I will replace it anyways.

But I'm glad you mentioned that. I checked the memory card earlier today and it seems the date was 01-01-2000 until it got GPS lock then corrected itself.

It is odd how it wont remember the date and syncing time with phone will get overridden by GPS time (or well set to 01-01-2000 before lock)

However, with it failing to record in the past I am not so confident in the unit. I will order a replacement GPS unit anyways.

 

[VIOFO-Support]

So I decided to open it up.

For anyone else who may be searching this up. The battery is a MS621FE its a rechargeable lithium manganese silicon battery. 3v, 5.5mAH. I will replace it anyways.

But I'm glad you mentioned that. I checked the memory card earlier today and it seems the date was 01-01-2000 until it got GPS lock then corrected itself.

It is odd how it wont remember the date and syncing time with phone will get overridden by GPS time (or well set to 01-01-2000 before lock)

However, with it failing to record in the past I am not so confident in the unit. I will order a replacement GPS unit anyways.

Except for the time issue, the camera seems not to record normally. What card do you use?

 

[JardaB]

How long has the camera been in operation? Befor replacing the MS621FE, measure its voltage !

 

[Nigel]

I don't drive my car as much as I used to (used to be daily, then a couple times a month, now a couple times a week).

Note that it is a rechargeable battery, it needs to be recharged occasionally. Every few months should be fine, but a full charge will take time, a 10 minute drive once per month is not enough. I think the recommendation is 24 hours for a full charge. So if you haven't been driving much, maybe take it into the house and put it on a mains charger overnight... And if you do replace the battery, give it an overnight charge before putting it back in the car...

 

[Nigel]

However, with it failing to record in the past I am not so confident in the unit. I will order a replacement GPS unit anyways.

The GPS has a clock battery too, but I don't think the time gets used for anything other than quickly finding the GPS satellites, so if the GPS battery has failed, the effect will be a slow lock onto the satellites, maybe 10 minutes instead of 10 seconds. Normally if you turn the dashcam off and then back on ten minutes later, the GPS should lock on within 1 minute.

 

[Michelin Man]

Except for the time issue, the camera seems not to record normally. What card do you use?

I mainly use Sandisk Max Endurance 256gb. However before I used Sandisk High Endurance 512gb and never had an issue (I needed longer recording time, but would also take the card out at least once a week).

The time being wrong isn't as much as an issue as the not recording. But the fact that there were no errors, and it would still beep when pressing the lock button.

I assume the time is used for organising the files. So when the date went to 01-01-2000 on a card that already had some 2025 video. It would constantly write over that single 01-01-2000 file.

How long has the camera been in operation? Befor replacing the MS621FE, measure its voltage !

I've had the camera since Jan 2023. It did used to run 9hr/day for the weekday (in regular mode not parking mode). Even in our hot summer which had caused the camera to shutdown on a few occasions.

Definitely will check the voltage before I de-solder it off the board.

Note that it is a rechargeable battery, it needs to be recharged occasionally. Every few months should be fine, but a full charge will take time, a 10 minute drive once per month is not enough. I think the recommendation is 24 hours for a full charge. So if you haven't been driving much, maybe take it into the house and put it on a mains charger overnight... And if you do replace the battery, give it an overnight charge before putting it back in the car...

Longest it would have been would be once a month but the drive would be longer than 15/20 mins as you wont get anywhere in less than 10 mins around here.

When the camera was acting up and not recording. Would have been back to a few drives (longer than 20 mins) a month.

The GPS has a clock battery too, but I don't think the time gets used for anything other than quickly finding the GPS satellites, so if the GPS battery has failed, the effect will be a slow lock onto the satellites, maybe 10 minutes instead of 10 seconds. Normally if you turn the dashcam off and then back on ten minutes later, the GPS should lock on within 1 minute.

I just opened the GPS module and what do you know. There is an even smaller battery in there. Ill wait for my replacement GPS module.

 

[JardaB]

Just for the record. SD cards need to be formatted regularly. Repeatedly rewriting files can be problematic; simply writing to a formatted medium is easier.