Frozen ThinkPad startup screen

[PhoenixR]

Got a hold of 3 T400 all of the same type id - and 2 out of 3 perform exactly identically strange (1 performs ok):
Right after powering on the ThinkPad startup screen freezes - and ThinkVantage button does not respond. No error messages, no beeps. Power and bluetooth leds are on.
What could be the problem?

[PhoenixR]

https://ibb.co/5xxZJWMH - the photo of the screen

[TPFanatic]

How long is it freezing?
If you press Esc does it freeze too?

These were among the first generations with Intel ME which can misbehave.

[PhoenixR]

How long is it freezing?
If you press Esc does it freeze too?

These were among the first generations with Intel ME which can misbehave.

I think freezing until power off is pushed. I don't think it's necessary to wait any longer than 5 mins so I never did more than that. No Escape, no Ctrl-Alt-Del work, no any other key. Keyboard and all the laptop seem to be unresponsive, although the screen, the leds, the drive and the fan are on.

[axur-delmeria]

Remove the hard drive and try again.

[PhoenixR]

Remove the hard drive and try again.

There's no hard drive But I'm sure this couldn't be the issue here as the laptop should seek any bootable source and let the access to the BIOS, too, by pressing ThinkVantage.

[TPFanatic]

could try reseating the CMOS battery and trying again. may or may not reset things.

[SMA]

if this had been a question about a t20 series ThinkPad I would say most likely a memory issue
but, as I haven't got much experience with errors on the t400 series, just take it for what it is.
Try swapping / reseating the memory modules.

[PhoenixR]

My initial guess was the keyboard failure maybe so I swapped it with another one - no change. Swapped the RAM - again, nothing.

Here, however, I've noticed a weird part of the laptop's behavior: laptop was disconnected from the power source. When I plugged the power adapter in - it started! I didn't press the Power button. Then instantly it re-started while having a black screen on and then the ThinkPad screen appeared - and it froze completely, with just the fan working. I had to hold the Power button to switch it off. This exactly behavior goes every time I plug it into power source(with or without battery attached, no difference) - so, what could that be?

PS I did try disconnecting the CMOS battery prior, it didn't help either

[PiZzA EnGiNeEr]

I had a T500 that did the same thing where it would hang at the boot screen. It turned out one of the side USB ports was damaged and one pin was shorting to the chassis ground. Had to bend the pin back so it wouldn't touch anything and then that was a non-usable USB port.

[PhoenixR]

I had a T500 that did the same thing where it would hang at the boot screen. It turned out one of the side USB ports was damaged and one pin was shorting to the chassis ground. Had to bend the pin back so it wouldn't touch anything and then that was a non-usable USB port.

This is a very valuable guess thank you PiZzA EnGiNeEr. Now I have to try and put your guess to work - not sure yet how to test the USB ports for shorting however... How did you test yours?

[RealBlackStuff]

LOOK at them, preferably with a magnifier.
Any crooked/broken/bent/missing pin, or dirt, or anything not right, should be visible immediately.

[PhoenixR]

Tnank you RealBlackStuff that really helped. Problem solved