02-10-2009 01:29 PM - edited 02-11-2009 04:20 PM
I have an IBM Thinkpad R51 Model 1836-Q4U which was purchased from IBM not Lenovo. Recently it has been behaving strangely; it will power up and then turn off unexpectedly. Moreover, it gets to the blue welcome screen, then shuts off. Every indicator light ceases to illuminate. In addition, the system does not post. A repair center says the motherboard is dead. After reading numerous posts, more often than not the motherboard is not at fault. Rather it is a component or capacitor which is to blame. Any similar experiences?
Thanks for your help
New addition to this post.
Get this, it started working today. I removed the top cover which houses the keyboard because I noticed it was warping, so it wasn't seated properly. Next, I had to remove every screw to release the Top covering which holds the keyboard. Lastly, I seated the top bezel, part which holds keyboard, then pressed the power button and it worked.
Ok, what is goin on here? It has been on for the past hour without any difficulties. What could have caused all this mayhem?
what type of hardware component could exhibit this behavior? Is it possible a screw was or was not touching something. Some people have written about screws touching metal components and causing short circuits. But, I think one of the screws, in the back, is supposed to be touching metal. The area I am describing is the back left part of the laptop. This area holds the lcd chip, I believe. The ribbon cable that extends from the LCD has a cihp or card attached to it; this chip attaches to the motherboard.
Is it possible that the motherboard has failed but the computer is operting fine?
Thanks for all the help and intelligent replies.
Oh, how do I add a post without editing the original post?
02-10-2009 02:52 PM
Generally, repair centers typically focus diagnostics on major building blocks - any failure on the system board from an individual chip, or even discrete component like capacitory, diode, resistor, etc will result in system board replacement as the diagnosis.
If you haven't already, I would start with some of the basics - test the output of your AC adapter, check the condition of your battery - glitchy / underperforming power supply components can lead to a voltage drop when the CPU ramps up power usage along with HDD, etc while booting. Voltage drop beyond a certain point and the system will shut down.
It could also be an overheat condition, so you could check to see if the fan is running normally, and that the heat sinks, etc are in place and making good contact. I would think that overheat would let you get a bit further and might not be quite as random. You could check and record the start up to sudden shut down times and see if they are longer when the system is cold. Does it run for shorter and shorter intervals if you keep trying to restart it?
I have seen systems with failed capacitors get to a certain point in the boot up and then fail as the point when the OS has started to load and the CPU is begining to do a lot more. Again, a voltage stability issue.
I might surf the web looking for refurb / good used system boards. As the price of new systems is falling rapidly, I imagine that part sellers will begin taking down their prices in order to make repair a reasonable alternative to replacements..
Others may have some additional thoughts for you...
02-10-2009 08:19 PM
I'd love to know the 7-character model number of R51 that we're discussing here, but let me state this for now:
a) It is time consuming (and therefore more expensive) to do a board level repair if you're a service center, especially since certain issues may go undetected until other are resolved. Planar swap may sound as a brutal solution, but it usually works well.
b) With no schematics available, one has to be lucky apart from being an excellent tech to correctly diagnose and resolve an issue without actually swapping the planar.
My $0.02 only...
02-11-2009 05:40 PM