Chosen Solution

I found a decent deal on a Lenovo X240 and found it had no HD and no memory. I found online the specifications for the memory and ordered the “Crucial 8GB (1x8GB) DDR3 RAM 1600MHz PC3L-12800 laptop Memory CT102464BF160B” for and installed a 256GB Samsung SSD drive I had already. Since I don’t have a power supply with the plug needed, I found Lenovo makes an adapter for the older yellow style barrel plugs and ordered one of those and just received. I plugged in the laptop with the 135W 20V Lenovo power supply and all I saw is the green LED turn on at the power button and the keyboard backlight flashes once and sounds like the fan is turning. The Fn LED flashes once green and stays green for about 4 seconds and then stays off. The red LED on the top of the screen “I” in Thinkpad stays lit red. I did the same with the 90W 20V Lenovo power supply though noticed the red LED on the top of the screen “I” in Thinkpad blinked red 3 times when plugging in the power supply and not even powering on or doing anything else. I just tested without the power supply plugged in and the same effect as with the 135W power supply… only with the external and internal battery.
Prior to plugging in, the power supply… the battery was dead and the laptop did nothing. I’m guessing one of the chargers must have charged one or both of the batteries somewhat. Finally, I tried to plug in an external known working monitor with no difference when I cycled power. The screen is black and never does anything in all the scenarios. What are your thoughts?

Hi @jafinch78 , Try disconnecting both the internal and external batteries and see if it starts just on the AC power. Here’s a link to the service manual for the laptop. Scroll to the bottom of p.60 to view the necessary pre-requisite steps and then the procedure to remove the internal battery. You should only have to disconnect it, not actually remove it. The manual also mentions an Emergency reset button hole in the Power system checkout on p.26 which you may have to operate as well to get things started. Also try removing the coin cell battery p.73 for a while (15-20 minutes - can’t find RTC reset pins) to allow it to get back to default BIOS settings in case they’re corrupted. (Check its’ voltage as well as it may also be flat and if it is as it non rechargeable it will have to be replaced). If you remove the RAM and the SSD does it behave differently when trying to start? If you can’t get it going at all, what was its’ working condition described as, when you bought it? Working but missing parts etc or “As is”, because if it’s a faulty systemboard you may have problems…

I didn’t want to answer this, but there is some potentially dangerous information in the previous answer you best not follow yet until you know if it has an SVP. Before you do ANYTHING with the system (especially the CMOS battery), get a external display that has VGA if at all possible; it can be DVI/HDMI only, but you will need a mDP adapter like this to get it going as the Thinkpad only has onboard VGA. We’ll get to why I want you to mess with literally anything else before the CMOS battery. It doesn’t need to be a new monitor - something used from a thrift store will work as long as it has the ports you need. Removing the CMOS battery on a Thinkpad 390E-XX30 is a potentially dangerous mistake; if you can recover the ATMEL chip, you can oops it. However, it is DEADLY on the XX40-present generation with Boot Guard. If you reset the ATMEL chip using the old methods, you will lock the machine out due to tampering and need a motherboard. If you removed it without being sure, this is a deadly error if you had a SVP :(. If I’m reading the previous thread right, pray it never came with a SVP.

Hi James. Just reading your post as I’m having a very similar problem with a T460. I bought mine with a cracked screen and no memory or ssd thinking I could fix it. The cracked lcd changed a slightly lighter shade of black when turned on. I bought a new lcd (which has an inverter attached) but it did the exact same thing. I would only notice that there was life in the lcd when I turned it off. Mine laptop gets power, the fan fires initially and the backlight on the keyboard illuminates but the the power dies after just over a minute. I’ve replace the lcd, the cable from the lcd to the motherboard. The motherboard. I’m thinking now it might be the power supply as I’ve noticed that the battery isn’t charging even though I have left the power supply plugged in. It could also be the cable from the battery plug port to the motherboard aswell. I’ve pretty much replaced nearly every component on this machine except for the power related items. It gave me some hope when I saw you posting. Did you narrow it down to definitely being the backlight? Did you end up finding a solution or did you just let is rest in peace? Kind Regards, Niall