Inspiron E7450 wierd Power on Issue

[HyBird]

I got a E7450 that was dead. First i removed accu and Bios Battery.
Then i pressed the power on button for 40 seconds.
After plugging in the power brick, it comes to live.
I plugged BIOS Battery and the accu back in to the computer in on state.
The laptop runs fine until i shut it down. Then dead again.
Now i have to repeat the precedure to get it runnig again over and over.
I was able to flash the latest A24 BIOS, no change of behavior.

At the Dell Forums is a rumor that this issue may be a engineering defect/design issue.

Is here somebody who has figured out what the issue is?
Or maybe you Guys have any suggestion for me?

Thanks.

[mcplslg123]

Re: Inspiron E7450 wierd Power on Issue

Without CMOS cell it's working. Correct?? But doesn't turn on if CMOS cell inserted. If yes, problem in RTC circuit

[HyBird]

Re: Inspiron E7450 wierd Power on Issue

thank you for your reply, i got the boardview software and the cad file for this board.
Can you point me in a direction where to search? Maybe a hint where to find the rtc circuit? is this a dedicated part or part of a big asic?

than you very much.

[mcplslg123]

Re: Inspiron E7450 wierd Power on Issue

Post or link the schematic/bdv here. Just type RTC in schematic search box and check each and every point it shows you. RTC reset has to be removed from PCH ,then only it will turn on. The major points are RTC_RST#/SRTC_RST#/INTRUDER ETC.

[HyBird]

Re: Inspiron E7450 wierd Power on Issue

Here is the link where i got the bordview file.
Can you show me the points i need to check?

Thank you very much. And best regards.

https://www.badcaps.net/forum/showthread.php?t=70511
.

[HyBird]

Re: Inspiron E7450 wierd Power on Issue

here the Boardview files as attachment...

[reformatt]

Re: Inspiron E7450 wierd Power on Issue

Check if the power button is actually working. I had similar behaviour on a Lenovo where the tracks on the side mounted button had broken. Most lappies will go through a CMOS reset sequence after the CMOS battery is removed, regardless of power button.