VOGONS

Search

Common searches

Toshiba Satellite Pro 410CDT Won't Boot - Caps Lock Indicator Flashes Repeatedly

Topic actions

First post, by weriov

Posted on 
User metadata
Rank Newbie
Rank
Newbie

Hi everyone - hoping someone might be able to help me with troubleshooting a non-boot behavior on my old Toshiba 410CDT. I've seen a couple threads relating to similar behavior on this series of machines, but none describes exactly what I'm encountering, so I'm hoping this new thread is okay.

Behavior is as follows: when I power on the system, both the power and battery/AC indicators light up green as expected, but after about two seconds, the Caps Lock indicator will also start to flash repeatedly and regularly (about one flash every two seconds, until the machine is powered off manually). The screen stays dark, and there's no beep indicating the computer has posted (I also don't get video if I hook the unit up to an external monitor while this is occurring). I've removed/reseated the main battery, expansion RAM module, hard drive, and internal CD-ROM drive, all without a change in behavior. The only thing that does change anything at all is removing the video board from its motherboard connector, at which point the Caps Lock indicator no longer flashes; I didn't know whether that was "something", so I swapped the video board for a different one out of a donor unit, but no change in the behavior there either.

I've done a cursory inspection of the motherboard and don't see any obvious electrical/component faults, nor do either of the MB batteries appear to have burst/leaked. As far as I can tell, everything is in the same condition it was in a couple months ago, when the machine was working just fine. And, as has been pointed out in the other threads, no mention is made of this "error code" in the maintenance manual, so I don't have any clue what it's trying to indicate.

Is anyone familiar with what might be going on here? Thanks!

Reply 2 of 3, by Thermalwrong

Posted on 
User metadata
Rank Oldbie
Rank
Oldbie

If it's flashing the caps lock key repeatedly, that should be a repeating reboot. To see where it's failing you can either use a parallel post code reader or LEDs wired to the data pins of a parallel port like this one: Re: What retro activity did you get up to today?
Since it's restarting very quickly, you'd probably need to video it and look at the post codes it listed. Those can be matched up with post codes in the maintenance manual.

The other thing to do is fully disassemble the laptop and inspect the front and back with the aluminium covers removed. Beware of flexing the board though once it's out of the case, I recently killed a 430 board being careless with that.
The bigger standby battery in particular has enough electrolyte to leak through to the back of the board or drip onto components. I recently fixed a 400CDT by finding that some electrolyte had leaked onto a little HC4066 component by the keyboard controller which had stopped the keyboard controller from working, replacing that component brought it back to working.

I got a lot of ideas from this blog post too and it's the same as your system: https://nielssp.dk/2019/09/fixing-410cdt/

Reply 3 of 3, by weriov

Posted on 
User metadata
Rank Newbie
Rank
Newbie

@thermalwrong - this is great info - I really appreciate it! I did have the entire unit apart when the issue first started, and I wasn't able to locate any signs of battery leakage (nor did it look like either of the standby batteries were leaking or bulging), but I probably should do that again regardless. I knew from the service manual that the POST codes could be read via the parallel port, but not having the Toshiba reader, I didn't know how to go about doing that - I tried fumbling at it with a voltmeter, but that obviously led to nothing, and I assumed I was up a creek because the reader would be impossible to find. It never occurred to me that there might be generic units out there that could be used in place of the Toshiba-branded part. I'm going to order one of those and see where it gets me.

Thanks again for the ideas and for the link to Niels's blog - they're extremely helpful, and I really do appreciate the response.

Go to top of page Go to top of page
Back to General Old Hardware
Close window
Close window