Strange IBM Thinkpad R51 issue with power adapter/motherboard...

[rml]

I have the following strange problem happening with IBM Thinkpad R51:

1)The laptop stopped responding to power-on button.
2) So I opened up the laptop and disconnect the keyboard cable from motherboard and reconnected it. Then it powered on and works fine. I then tested it many times turning it on and off and laptop seems to be working 100% fine.

3) Then I plugged in the power adapter. Then laptop stopped responding to power button again!!!

4) While power plug is still attached, I removed the keyboard cable from motherboard and reconnected back in. It then let me turn on the laptop and let me powered down and everything looks fine. When I unplugged the power adapter, the same issue happened again.

So, I can keep it running if I never plugged in the power adapter OR only use the laptop with the battery. (but it will not work if I removed battery and inserted back in)

I even bought a brand new power supply but it did not help

Is the motherboard bad or the power switch on the keyboard is bad?

Any idea?
Hope you follow what I wrote above.

thanks in advance
rml

 

[DarkThinker]

Originally posted by: rml
I have the following strange problem happening with IBM Thinkpad R51:

1)The laptop stopped responding to power-on button.
2) So I opened up the laptop and disconnect the keyboard cable from motherboard and reconnected it. Then it powered on and works fine. I then tested it many times turning it on and off and laptop seems to be working 100% fine.

3) Then I plugged in the power adapter. Then laptop stopped responding to power button again!!!

4) While power plug is still attached, I removed the keyboard cable from motherboard and reconnected back in. It then let me turn on the laptop and let me powered down and everything looks fine. When I unplugged the power adapter, the same issue happened again.

So, I can keep it running if I never plugged in the power adapter OR only use the laptop with the battery. (but it will not work if I removed battery and inserted back in)

I even bought a brand new power supply but it did not help

Is the motherboard bad or the power switch on the keyboard is bad?

Any idea?
Hope you follow what I wrote above.

thanks in advance
rml

Just out of curiosity, this might not be relevant, but can you try resetting your BIOS to defaults even though you didn't make any changes there, but just for testing's sake do that, and also test updating your BIOS to the latest one from IBM (I suggest burning a BIOS ISO to a CD and flashing the BIOS by booting from CD, but be careful you don't lose power while that is happenning ). Now report back so that we can eliminate variables here.

You may have a bad battery, when it's getting plugged in while AC is on it's sending a false signal of somekind that forces the laptop to do a safety shutdown. If your updated BIOS doesn't help, then I would definitely check if your battery's 1 year warranty still applies, if so call IBM and inform them of the issue they would able to determine better than me the source.

 

[rml]

Just out of curiosity, this might not be relevant, but can you try resetting your BIOS to defaults even though you didn't make any changes there, but just for testing's sake do that, and also test updating your BIOS to the latest one from IBM (I suggest burning a BIOS ISO to a CD and flashing the BIOS by booting from CD, but be careful you don't lose power while that is happenning ). Now report back so that we can eliminate variables here.

You may have a bad battery, when it's getting plugged in while AC is on it's sending a false signal of somekind that forces the laptop to do a safety shutdown. If your updated BIOS doesn't help, then I would definitely check if your battery's 1 year warranty still applies, if so call IBM and inform them of the issue they would able to determine better than me the source.[/b]

Thanks for the advice, I will try to update BIOS tomorrow. laptop was two years old already, so out out warranty.

 

[DarkThinker]

Originally posted by: rml

Just out of curiosity, this might not be relevant, but can you try resetting your BIOS to defaults even though you didn't make any changes there, but just for testing's sake do that, and also test updating your BIOS to the latest one from IBM (I suggest burning a BIOS ISO to a CD and flashing the BIOS by booting from CD, but be careful you don't lose power while that is happenning ). Now report back so that we can eliminate variables here.

You may have a bad battery, when it's getting plugged in while AC is on it's sending a false signal of somekind that forces the laptop to do a safety shutdown. If your updated BIOS doesn't help, then I would definitely check if your battery's 1 year warranty still applies, if so call IBM and inform them of the issue they would able to determine better than me the source.[/b]

Thanks for the advice, I will try to update BIOS tomorrow. laptop was two years old already, so out out warranty.

I would still call IBM anyways, don't give them info they don't ask for, I am assuming you could still get some sort of tech support even though you are out of warranty, tell them you want to order replacement parts through them, but don't what part is defective to begin with, that way maybe they would help you troubleshoot it at least.

 

[WackyDan]

There is a voltage controller on the THinkpad... It regulates where and how the TP gets it's power. Sometimes they flake out. You'll probably need a new planar.