Lenovo X1 Carbon 2. Gen no Display!

[Ariu]

Notebooks is powering on without post.
All power rails present, only L1 (Vcc_CPU_Core) measurement 0,112 V (resistance on L1 120 ohm).

Flashing New bios no different.

Mainboard: LMQ-1 MB 12298-2 48.4LY07.021

[JaroTech]

Re: Lenovo X1 Carbon 2. Gen no Display!

Hi, have you checked all voltages on the U16 chip to see if they are all good?

[Ariu]

Re: Lenovo X1 Carbon 2. Gen no Display!

Hi, have you checked all voltages on the U16 chip to see if they are all good?

Hi,

L1 #pin2 CPU side one leg desoldered and u16 measurement are like this:
Pin1: 0V
Pin2: 0V
Pin3: 1,8V
Pin4: 1,8V
Pin5: 0,8V
Pin6: 1,8V
Pin7: 1,7V
Pin8,9,10,11: 5,1V
Pin12,13,14,15: 0,5V

[leadslinger2112]

Re: Lenovo X1 Carbon 2. Gen no Display!

reflow ram chips with a hot air station, had one doing the same thing and that was the only fix that worked for a while. the ram failing are a common issue with the gen2 x1 carbons

[piernov]

Re: Lenovo X1 Carbon 2. Gen no Display!

Reflowing RAM usually won't fix it, it will fail again shortly after. Problem appears to be CPU-related.