Cellular Modem runs real hot, lots of battery

Yes, all firmware. No, my cellular modem does not run hot, but I stay off-grid whenever possible so I never really get an accurate idea if it does or not.

I assume that the software is already up to date. That in turn will then raise the question as to whether you have enabled suspend, and I think that in turn will then raise the question as to whether the modem firmware is up to date.

Even on my iPhone, battery drain is higher when spending a lot of time in poor-signal areas (such as is common when driving longer distances in my country).

I guess the Librem 5 at least gives you the opportunity to run some hacky shell script to test a hypothesis that time in poor-signal areas correlates with rate of battery drain.

What about a day where you spend the entire time in the same place, while getting good signal? That would certainly be a more controlled environment to investigate in.

I wonder if the ambient temperature makes it worse? (Does it run hotter in Phoenix AZ?)

(And it isn’t just a Montserrat song by Arrow.)

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Yep, software up-to-date. I have enabled suspend. It works well. No idea if the modem firmware is up-to-date. How do a I check that?

Yep, it drains faster in poor signal areas. Thank you. That is a checkbox for me. The battery drain is much better when stationary and in a place with good, consistent signal. I was at my office in the city and that was much better than at home. Check.

I am interested in exploration of shell scripts and/or user tinkering with apps or operating system and their effect on battery.

I mean sure. The outside temperature does have an effect. No doubt.

Is it possible the modem isn’t seated properly and it could be working harder than it should? Just a shot in the dark here.

I can check. Thanks.

Here is what I am running for firmware:

firmware revision: MPSS.JO.2.0.2.c1.1-00032-9607_GENNS_PACK-1.351938.1 1 [Nov 26 2020 02:00:00]

Is this the most recent version?

It looks like this post is what I am really looking for: L5 Modem BM818 - Open Firmware

Although I am not allowed to hold my phone while driving, I do recall it becoming considerably warmer when I stream music on the road.
I don’t remember which part gets the warmest. But I will check it out this summer when we go on our vacation.

Ok. That is about what my experience is. Sometimes it gets so hot in the car that I can’t charge. Which is real annoying. The experience is not terrible. I just wish the battery performance was better when using cellular.

The Purism forums got restored to a previous backup snapshot, so if you have not already, email support@puri.sm about updating your modem firmware. If necessary, I can also forward you the same email they sent to me.

A quick report from my climbing gym: yesterday I streamed music for two hours (both cellular data and wifi switched on) without any noticeable temperature rise.
I know, this is not the same as streaming via cellular only, but I wanted to share the info anyway

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As an update to this. I update my modem firmware and I have noticed a significant improvement on: 1. my phone call quality has been improved and I think it corresponds with VoLTE better. 2. I think the performance of the modem is a little better in terms of consumption of battery. I have not real metrics to measure my beliefs.

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Good to hear anyway.
I did put the L5 to the test on a long drive.
Streaming music on the cellular, while charging, it reached 48 degrees Celsius. That is pretty hot. It stopped charging. But it did not get any hotter than that.

Hi can you share the modem firmware version?

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I believe it is:


Please make sure.


@joao.azevedo how get it in touch with you to update one Librem 5 modem with YCSN0_M100E_1ACD_B325_V1.0.0.2_20220930 version as my L5 modem still 2019?

That is number the BM 818 tool gives me.

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please email support@puri.sm