Toshiba Satellite Pro 430CDS won't start

[racer914]

Hi all,

I am new to the forum, and hoping to get some help. I have a Toshiba Satellite Pro 430CDS laptop with a Pentium and running Windows 95 that worked until recently, but now won't start. I have this laptop to program some older aftermarket automobile engine management software that doesn't play nicely with newer computers. This laptop generally worked well for me for a year or two after I got it. Now when I try to turn it on, it briefly makes the usual startup sounds, including what I think may be the hard drive momentarily trying to start. Then nothing aside from what I assume to be a fan running. Nothing ever appears on the display.

A few observations/notes:
- I tried plugging in a modern monitor using the VGA plug to rule out a display issue. Nothing.
- Before the computer stopped working, I was getting "Bad RTC battery" errors on each startup, which I understand is related to the CMOS. I've since read that if the CMOS battery is far enough gone that it can can odd behavior possibly including not starting up. Could it cause the problem I'm experiencing?
- I recall getting some hard drive errors not long before it stopped working. It happened a couple times. I was prompted to perform a repair function like chkdisk (but don't recall exactly), and each time the computer seemed to function normally again after that.
- I managed to download a Toshiba service manual for this model, and the steps suggest that the display could be the issue, but I think I may have ruled that out testing with the external monitor.

Any suggestions for things to check appreciated! Thank you.

Scott

 

[ph4nt0m]

Some notebooks don't even POST without a good RTC battery, though most do. It shouldn't be complicated to replace it in your Toshiba. I'd also check the power supply.

 

[Kakemoms]

Some notebooks don't even POST without a good RTC battery, though most do. It shouldn't be complicated to replace it in your Toshiba. I'd also check the power supply.

I guess you can rule that out since he had it booting without the RTC (=real time clock) backup battery working bdfore that. Usually the config setting will go to default and show you a config screen, but it depends on wether the config needs the battery or not. If I remember correctly, holding down one of the function keys (+ Fn?) during boot should take you into the satellite config screen. I don't remember the exact key, but they have markings on them showing their alternate functions.

The external display won't work until you switch it on. That is also done through one of the function keys I believe. I can look at my own satellite(if I can find it) and tell you more about the exact key combination later.

 

[racer914]

Thanks guys. Is it possible that the RTC/CMOS battery was "good enough" before to at least run the computer and it just became insufficient recently?

I did try removing the main power battery. The computer still won't boot.

Thanks for the point about the monitor button. It looks like F5 performs that function. I'll have to head to the library to try the external monitor again.

 

[genera_jitters]

Hey! also new to this forum, just picked up a 435cds with the same exact issue. they are the same computer with different software/warranty options , would really like to get it working. i read on this link that there was a issue regarding the original battery causing issues and the pc wont even post. took the battery out/ checked multiple monitors and even tried the f5 button got nothing.

http://www.minuszerodegrees.net/manuals/Toshiba/Toshiba.htm#435

 

[GiGaBiTe]

Thanks guys. Is it possible that the RTC/CMOS battery was "good enough" before to at least run the computer and it just became insufficient recently?

Yes.

Quality CMOS batteries can last for decades before the voltage gets low enough to not maintain the CMOS settings. I have some 30 year old Tadiran lithium batteries which still have enough of a charge to work today.

My 1994 Zeos 486 motherboard just recently had the RTC battery go bad inside the Dallas time chip, which makes it 25 years old.

 

[Gered]

I have a Toshiba 430CDT that I use without issue with both the RTC and Suspend (or whatever it's called) batteries removed and it boots just fine. The RTC battery I had still actually worked fine but since it is now over 20 years old, I didn't want to risk leaving it in anymore in case it started leaking out all over the motherboard.

I cannot be 100% certain in your case, but given that the difference between my 430CDT and your 430CDS is literally just the type of display, I'd guess the RTC battery is not the problem.

 

[modem7]

I have a Toshiba 430CDT which has experienced three different causes of the 'no display' symptom. For all three causes, I could hear Windows 95 starting up (there was over a minute of hard drive activity that could be heard). I list the causes in the 'Known problems' section of [here].

 

[racer914]

I'm just getting back to this after a couple months. From Gered's post above, it sounds like the RTC battery may not be the issue after all. I am suspicious of the hard drive. Before the laptop failed, I was periodically getting errors that sent the laptop into a disk repair mode. The hard drive is a Toshiba HDD2712 B. Is there a way to test the hard drive to confirm whether it is OK? Thanks …

Scott

 

[racer914]

Would a failed hard drive be a reasonable candidate to produce the following symptoms?
- When I attempt to turn on the computer, it seems to do the initial steps of the startup routine.
- I hear what may be an attempt to start the hard drive, but it quickly stops. No further activity except what I assume is the fan running, and nothing appears on the screen.
- There is a light at the top of the keyboard that appears to indicate hard drive activity. When I try to start the computer, the light briefly flashes at the same time as what sounds like the hard drive noise mentioned in the bullet above.
- Shortly before the computer stopped working, I experience several instances of the hard drive doing into when I believe was a hard drive repair routine. Perhaps the hard drive was failing.

I have the hard drive out but am unsure how to troubleshoot. Any guidance appreciated!

Thank you.

Scott

 

[modem7]

A POST code reader on the parallel port can sometimes help. On my functional 430CDT, powering it up with one of [these] connected to the parallel port, results in POST codes being displayed, per pages 2-10 through 2-12 of the 430's maintenance manual. Available on eBay (e.g. item 283223726107).

 

[modem7]

It is possible that two distinct problems are present, one relating to the hard drive, and one related to video. Maybe both are related to each other. But, I think that you should treat them as distinct. I think the 'no video' symptom is the one to target first. So, with that in mind:

As you now know, a bad main battery in the 430 series can cause the 'no video' symptom, and accordingly, you removed the main battery and still had the symptom.

I did an experiment with my functional 430CDT, which was to remove more stuff. So, with all three batteries and the hard drive removed, I observed:

1. I plugged in the AC power cord. The 'AC power' LED above the keyboard (at far right) turned on (green).
2. I pushed the power button. The 'power' LED above the keyboard (at far left) turned on (green).
3. A few seconds later, the 'CAPS lock' LED above the keyboard flashed on three times.
4. About 5 seconds later, I saw a couple of lines of text momentarily appear on the screen. The text starts 'Toshiba Video BIOS'.
5. The aforementioned text was very quickly replaced by a flashing underline cursor at the far left of the screen. The POST code reader on the parallel port showed code 5A (right LED block).
6. About 2 minutes (minutes, not seconds) later, the 'disk' LED above the keyboard flashed on once, then the cursor was replaced by a message starting '**** Bad check sum (CMOS) ****'. The POST code reader on the parallel port showed code FF (right LED block).

I repeated the above sequence a few times (to prove repeatability).

Do you see see the status LED's above the keyboard behave per steps 1, 2, 3, and 6, above ?

In doing the above sequence many times, the video problem in my primary 430CDT resurfaced a few times. In most cases, there was something on the screen (lines, or strange patterns, or corrupted text), but once, the screen was just black. in all cases, the fix was to slightly flex the display, noting that sometimes the fix was BOTH to flex the display and then power off/on the 430CDT. One of these days, I will pull apart the display and attempt to fix this intermittent problem.

I have another 430CDT that I bought for spare parts. It has a 'no display' symptom, which I believe may be due to a faulty LCD inverter. Something else to get around to. (And the backup/resume battery had leaked, damaging the keyboard connector on the system board, and damaging the ribbon cable on the keyboard.)

 

[racer914]

Thank you, modem7. Your help is much appreciated. I tried the test you mentioned above, with all three batteries and hard drive removed. I timed my test at 4 minutes and tried it several times. See results below, with my comments in CAPS.

I did try flexing the screen a number of times during and between rounds of testing as you suggested.

1. I plugged in the AC power cord. The 'AC power' LED above the keyboard (at far right) turned on (green). I SEE THIS
2. I pushed the power button. The 'power' LED above the keyboard (at far left) turned on (green). I SEE THIS
3. A few seconds later, the 'CAPS lock' LED above the keyboard flashed on three times. I DID NOT SEE THIS
4. About 5 seconds later, I saw a couple of lines of text momentarily appear on the screen. The text starts 'Toshiba Video BIOS'. NOTHING EVER APPEARS ON MY SCREEN
5. The aforementioned text was very quickly replaced by a flashing underline cursor at the far left of the screen. The POST code reader on the parallel port showed code 5A (right LED block).
6. About 2 minutes (minutes, not seconds) later, the 'disk' LED above the keyboard flashed on once, then the cursor was replaced by a message starting '**** Bad check sum (CMOS) ****'. The POST code reader on the parallel port showed code FF (right LED block). I DID NOT SEE THE DISK LED FLASH OR ANYTHING ON THE SCREEN

After reading your comment about the resume battery leaking, I looked at mine closer and noticed evidence of leakage. I also see some evidence of corrosion on the circuit board (mother board?) under where this battery sat in the computer. Does this along with the test results above suggest the mother board is damaged?

 

[modem7]

With the 'power' LED being on, I think you can safely assume that the power supply unit (Toshiba name it the "AC PS Unit") is functional. I could not see anything in the maintenance manual where one could make voltage measurements to be absolutely sure.

The fact that you did not see the 'CAPS lock' LED flash (nor the later flash of the disc LED) suggests to me that the system board is either not starting, or is starting, but one of the early tests in the POST is failing. If the latter, the 'parallel port monitoring POST board' that I referred to in post #11 should reveal that.

After reading your comment about the resume battery leaking, I looked at mine closer and noticed evidence of leakage. I also see some evidence of corrosion on the circuit board (mother board?) under where this battery sat in the computer. Does this along with the test results above suggest the mother board is damaged?

It suggests the possibility.

 

[racer914]

Would it be a fool's errand to try cleaning the mother board to see if it returns the computer to normal function? Or time to find a replacement?

 

[modem7]

Would it be a fool's errand to try cleaning the mother board to see if it returns the computer to normal function?

Worth doing because you may then see a copper track (or more) that has been eaten through. If the case, there may be someone local who can repair the track for you.

 

[kahuna]

Dear all,

I've got a 430CDT with the same boot issue described in this thread. I can see all of these points happening on my laptop:

1. I plugged in the AC power cord. The 'AC power' LED above the keyboard (at far right) turned on (green).
2. I pushed the power button. The 'power' LED above the keyboard (at far left) turned on (green).
3. A few seconds later, the 'CAPS lock' LED above the keyboard flashed on three times.

However, after the three flashes of the CAPS lock led, nothing happens, I just got a black screen, it doesn't matter how much time I wait.

The hard disk drive was dead in my unit, so I replaced it with a 2GB compact flash card connected over an 2.5" IDE adapter.

These are some things I tested. I'm afraid all of them ended up with the same result, black screen:
- No hard disk drive
- 60GB IDE disk drive
- Used an external monitor via VGA connector
- Removed the internal CDROM
- Removed all batteries: Resume, CMOS and main battery
- Connected only the main battery, no AC power
- Removed the RAM expansion

I also tried with many combinations of the above, different disks with and without main battery, with and without the CDROM etc.

The only exception to the black screen behaviour is when I press and hold F12 before starting the laptop to enter in BIOS/CMOS write mode. That works, I can see a message that prompts me to write a new version. I don't have a floppy drive though.

I ordered a parallel port diagnostic tool to see the code the laptop is throwing, but in the meantime I just wanted to ask if you can think of any possible next steps to troubleshoot what could be the problem.

Thanks!

 

[modem7]

I've got a 430CDT with the same boot issue described in this thread. I can see all of these points happening on my laptop: ...

Interesting to me is that the only situation in which you see anything on-screen is when you use F12 to get into 'BIOS update' mode. I would never have thought about trying that. It certainly suggests that the display subsystem is functional.

Regarding the 'CAPS lock' LED flashing on three times. In the IBM AT, the keyboard related LED's flash twice, first when the IBM keyboard receives power (the IBM keyboard does a self test), then later when the the motherboard's POST issues a self-test command to the keyboard. As an experiment, on my functional 430CDT, I used DEBUG to issue a self-test command to the keyboard (hoping that the same port and command are used [for compatibility reasons]). The 'CAPS lock' LED flashed once (not three times). To me, that suggests that at least two of the 430's three flashes of the 'CAPS lock' LED, are due to code in the 430's motherboard POST.

I ordered a parallel port diagnostic tool to see the code the laptop is throwing, but in the meantime I just wanted to ask if you can think of any possible next steps to troubleshoot what could be the problem.

I cannot think of anything beyond what you have already tried.

 

[DeltaDon]

With the HDD removed you should still have a POST screen on the LCD. So the HDD could be bad, but until you get a POST screen you are going in circles. Many things can prevent POST. The motherboard could be dead from a failed component, the power supply could be bad and it could be a bad CMOS could have leaded it's guts onto the board and eaten one or more traces. Plus simple things like a failed connector or even a shorted HDD/floppy or RAM pulling down the power supply voltage(s). Also, a dark LCD can be working without the backlight powering up. If you look closely with some room light hitting the screen at an angle you might see a very dim display of POST or other stuff. In that case the laptop is working, but the backlight bulb or it's power source are dead. Also some early laptops needed the main battery to be in place or they'd not boot. So a dead battery can cause problems with these laptops.

 

[kahuna]

Hi guys,
Thanks a lot for your responses!

Yep, I believe I have something fried internally which is preventing the laptop from booting.
We'll see what the LPT diagnostic tool says, if the shipment manages to arrive...

Regards.