Mostly dead A31p - turns off in 10 seconds - fan error

[rkawakami]

Haven't spent much time here in the RAG conference, but I am trying to change that . Got an eBay-sourced A31p today. A 2653-N6U that exhibits the following symptoms:

- powers on but turns off by itself after about 10 seconds
- two short beeps
- dead backlight; IBM splash screen is visible on the LCD under bright light
- no external video during the splash screen but it does show a fan error message just before it shuts down; lack of video for the splash screen may be due to my monitor not being UXGA capable - the "fan error" message appears to be displayed in text mode but my LCD monitor says "out of timing".

As per searching the archives, there's no problem with a short in the USB ports. I've removed all easily removable parts (modem/wireless, ethernet, bluetooth, memory, Ultrabay, hard drive, CMOS battery) and the system throws the expected 1-3-3-1 beep sequence (no memory) but remains on for longer than 10 seconds. I let it go about 45 seconds before I turned it off. No use cooking the CPU as the fan is definitely not spinning. Installing one 256MB memory module reverts back to the two short beeps and the 10 second automatic shutoff. Backup battery appears to be good; 3V and plenty enough current.

At this point I'm going to tear apart the system (when I get the time) and verify that the fan is good or get a replacement. After that, source a 26P8133 inverter for the lack of backlight and hope that's all that's wrong with the display. This seems to be a rare part as there's zero/zip/zilch/none/nada/nil/null on eBay at the moment. I know that the HMM says this part is required for the 15" UXGA IPS display but it also says that the same 26P8133 is used in the 15" SXGA+ IPS screen, along with the 62P9872. This seems to indicate that those two inverters are interchangable.

So, has anyone tried using the 62P9872 with a UXGA IPS screen?

[AlphaKilo470]

Sounds like a fun project you have on your hands. In my experience, the A30/A31 has a rather brittle chassis so be careful with it. However, if you manage to get that computer running, I'm sure you'll love it. The A31 is a powerful machine and can do quite a bit.

I'm not sure if it'd work or not but I have an inverter with FRU # 26P8132. It was pulled from a dead A30 with 14" XGA screen.

As for the fan error, definitely try testing the fan before buying any new parts. I used to have an A21m that had a working fan installed but the circuitry on the motherboard that controlled it was kaput.

[rkawakami]

Well, the exploratory surgery is finished. The patient arrived DOA and looks like is going to remain that way . Here's a site with all of the gory details:

http://www.kawakami-ca.com/ibm_a31p/

The short story: someone used the wrong screw to attach the keyboard bezel. Looks like a new motherboard will be required.

[vanaya]

Great pictures, that microscope looks like a great toy!!

[AlphaKilo470]

So what will it take to get that screen from you?

[rkawakami]

At the moment, you will have to pry it out of my cold, dead, hands .

I'm trying to round up a proper motherboard and see just how much is working on this puppy. I have an 2652-C3U A31 with a 15" XGA and an assumed loose GPU problem. System works but sometimes has random blocks and lines on the display. I was hoping to use the A31 as a temporary transplant patient and see if the A31p's UXGA screen is working or not. By reading this thread:

http://forum.thinkpads.com/viewtopic.php?t=21740

I see that it's not possible to swap these panels .

[Harryc]

This is a perfect example of why it's important to label/keep track of exactly which screws go where upon disassembly/reassembly. Good job on the problem determination Ray.

[AlphaKilo470]

I used to have an A30 with a big hole in the wrist pad because somebody used the wrong screw and not only punctured the plastics but broke off the screw thread.

[rkawakami]

Got a T23 with a small dimple in the palmrest. Somebody (named, me) used too long of a screw to re-attach the CMOS battery .

<snip>.. someone used the wrong screw to attach the keyboard bezel.

Actually it's not the keyboard bezel but the "Y-shaped" brace that attaches to the right side Ultrabay and just behind the PCMCIA card cage. I've only taken apart an A31 once before so I didn't know exactly which piece was secured to that screw bracket.

[fongj]

Well, the exploratory surgery is finished. The patient arrived DOA and looks like is going to remain that way . Here's a site with all of the gory details:

http://www.kawakami-ca.com/ibm_a31p/

The short story: someone used the wrong screw to attach the keyboard bezel. Looks like a new motherboard will be required.

Very cool pictures. I hope the whole "take-apart, investigate, and diagnose" process was fun for you... (of course it was, or else you wouldn't have bought the machine off eBay to try to fix!).

Did you consider getting one or two short lengths of wire and seeing if you can restore any/the connections destroyed by the screw damage? (Maybe its just me, being a tightwad, that would think of this option). As you mentioned, there's also the possibility that there's a whole missing component there too... but if you have a replacement motherboard to compare to later, that should be easy to confirm.

[rkawakami]

I hope the whole "take-apart, investigate, and diagnose" process was fun for you... (of course it was, or else you wouldn't have bought the machine off eBay to try to fix!).

I enjoy a good mystery! And I'm cheap (but not easy!). I thought that maybe the problem was something simple (it was) and easy to fix (wrong on that count). Plus I'm a sucker for SXGA+ and UXGA screens.

<snip>... but if you have a replacement motherboard to compare to later, that should be easy to confirm.

Which is why I just obtained another A31p motherboard. Hopefully I can determine the amount of damage done and by signal tracing, install some patch wires like you suggested. The damage that the extra long screw did was to eat through at least two printed circuit layers (one on top and one buried in the middle of the board). These boards can typically be FOUR layers (top, bottom, two in the middle) so I'm (again) hoping that it will be something easy to fix.

[RWDPLZ]

Sorry to bring a thread back from the dead, but THANK YOU!!! I was FINALLY able to figure out what was wrong with my A31 motherboard with the fan error. I took it down to the bare motherboard, and there was the damaged part, just like your A31p. That was driving me nuts. Now I've pulled every usable part off it, I'm ready to smash the bare board with a large hammer

[rkawakami]

I was just thinking that ("thread from the dead") when I saw it pop up on my index page and before I opened up the thread to read your post. It looks like a common problem with the A31 systems if people are not careful in putting the right screw back where they belong. I still have not ripped up this system and the other A31p I bought as a guide. Maybe one day when I have nothing else to do... If you really don't want that board, hang on to it as I'm sure somebody else might like to take a crack at it (and I don't mean with a hammer ).

[Robbyrobot]

The short story: someone used the wrong screw to attach the keyboard bezel. Looks like a new motherboard will be required.

Don't you just love "Ingineers" who design such systems? I've already commented once on the "intelligence" of people who design systems in such a way that a screw can cause permanent damage.