Currently I have a similar issue, I have a siemens field pg m6. I had it running fine for more than 1 year no issues. 

one morning it decided not to restart. I tried to remove the battery and start it with no battery(only the charger). it booted fine.

I ordered a new battery and it was the exact same battery (SP306) plugged in, it booted fine, and only lasted 6 months

this morning it had a boot error( default boot device missing or boot failed), I tried booting with no battery, my device booted fine, I need assistance as to what my options are regarding the pg and its battery, since its outside siemens warranty now.

I this something is wrong with the pg charging circuit/system, since with the battery in it doesn't boot, and it seems to ficker the display slightly, like its shorting somewhere

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Split from Simatic Field PG M6 - Will not start (PC dead).

Hello Seth_automation,

check the settings in BIOS. Change the adjustment in BIOS> Advanced> PCH-IO Configuration> DeepSx Power Policies "Enabled in S4-S5". With the setting described, the battery lasts> = 1/2 year without charging.

With best regards
Cicero

We purchased 2 new M6 Field PG's last summer. It was late last year before we were moving to put them in service. They  were fully charged when they were put in service. At the end of December, when I went to use them, both units had dead batteries. I charged them both, and then found that even performing a Windows 10 shutdown, the batteries would lose about 10 percent of their charge each day. I made this change to the BIOS of one of them, then tested again and this resolved the issue (same charge level as the day before). I made the change on the other one today, but it looks like this has completely resolved the issue for us.

Thank you for posting this.

Currently same issue. Will order a new battery.

Sometimes you are able to boot with the supposedly bad battery but the screen will flicker as if the battery/charging circuit is trying to do something. And you will also get the "boot device missing".

95% of the time my M6 was connected to the charger.

Seth_automation

Currently I have a similar issue, I have a siemens field pg m6. I had it running fine for more than 1 year no issues. 

one morning it decided not to restart. I tried to remove the battery and start it with no battery(only the charger). it booted fine.

I ordered a new battery and it was the exact same battery (SP306) plugged in, it booted fine, and only lasted 6 months

this morning it had a boot error( default boot device missing or boot failed), I tried booting with no battery, my device booted fine, I need assistance as to what my options are regarding the pg and its battery, since its outside siemens warranty now.

I this something is wrong with the pg charging circuit/system, since with the battery in it doesn't boot, and it seems to ficker the display slightly, like its shorting somewhere

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Split from Simatic Field PG M6 - Will not start (PC dead).

Happened again almost one year later. The battery cells or the charging circuit is defective. No warranty provided. Please avoid the model M6. It's an unreliable Siemens product, not rated for professional work and may shutoff during a startup job. Better keep the old M4.

Some updates.

Local Siemens doesn't stock the item (nothing new). Delivery date is in reality a moving target (nothing new). Have to source it from second hand.

Third party analysis indicates heat damage. It just so happens the processor cooling solution is sitting just above the battery. It's designed to fail so it seems. There's no definitive solution.

 Remedies are avoiding battery heat soak:

• Using third party software to modify fan profile and lower the idling temperature. 
• a laptop cooling pad (if you leave it on, stationary for a long time).
• heatshield between the back of the battery and internal case.
• thermal pads between battery and removable door.

Hope this helps.

Hi samuelbb,

I sadly note that I'm not the only one having problems with the PG M6...I bought it in June 2019...in July I had to go to Ford in Chicago...luckily I brought my PC with me Acer with all Siemens sw ... At a certain point the PG would not restart anymore (new PG) ...

there was no way to make it work...Back in Italy I sent it to Siemens assistance...they changed the motherboard...new PG...

After a year I had problems with the battery...I had to remove it from the PG because otherwise it wouldn't restart....after about six months I put it back....everything seemed to be fine...l last year again...and the battery costs 400 euros...let's say that for a PG that costs around 6000 euros, I expected more...Siemens totally let me down...me in their place I would have been ashamed to sell such ciofeghe...shame on you !

Roby

塞缪尔布

一些更新。

当地西门子没有库存该商品（不是什么新鲜事）。交货日期实际上是一个不断变化的目标（这并不是什么新鲜事）。必须从二手货中获取。

第三方分析表明存在热损坏。碰巧处理器冷却解决方案位于电池上方。看起来它注定会失败。没有确定的解决方案。

 补救措施是避免电池热浸：

• 使用第三方软件修改风扇配置文件并降低怠速温度。 
• 笔记本电脑冷却垫（如果您将其长时间保持固定状态）。
• 电池背面和内壳之间的隔热罩。
• 电池和可拆卸门之间的导热垫。

希望这可以帮助。

 good suggestion