- Nov 28, 2017
- 2
- 0
- 510
Situation:
My Toshiba satellite P855-34Q was bought in 2015. I used it for a couple of weeks, but then got a laptop from work. The Toshiba has been kept since then in a drawer in my living room. Dry, no temperature swings, dust free. Same place where I keep my work laptop and where my husband keeps his 10 year old Toshiba. This week, I needed it for some virtualization (which my laptop from work nor my husband's laptop is good for, not enough RAM)
Took it out, put the battery in, plugged the AC in and connected it to the power net. I got an orange charging light.
I tapped the power button: White light in the power button, white light on the front panel (next to the charging light). But after only two or three seconds, the light on the power button and on the front, goes out again. Nothing appears on the screen, no beeps, no sounds of fan or hard drive.
This same behaviour is still present after I tried the following steps:
- Measured the voltage on my CMOS battery. It was only 2,14V, so too low. When the laptop is charging though, the voltage on the CMOS battery climbs tot 2,68V.
- Left it to charge until the charging light was white, indicating fully charged. Turned it on, same behaviour.
- Took the battery out and measured its output. Normal output voltage
- Measured the output on the AC adapter. I measure a voltage of 19,38 Volts, so normal.
- Without battery, only connected through the AC adapter, tried turning it on. Same behaviour.
- Without the battery, and without AC feed, I held down the power button for over a minute to discharge anything residual. Plugged in the AC, turned it on, same behaviour.
- Same thing as the previous step, now with only the battery. No success.
- Took out the hard drive, tried turning it on. Same thing happens, power light goes out again after three seconds (AC and battery tried separately)
- Took out one RAM stick, tried again, took out second RAM stick, tried again, swapped each RAM stick to another bay, tried again (again, as well with AC only as with battery only).
- Put another CMOS battery in parallel over the drained one to get 3V. No success.
- Measured if there was a drop in CMOS battery output voltage when turning the laptop on: no drop in voltage.
- During the three seconds when the "on" lights are actually on, tried to open the CD drive, nothing happens.
- During these three seconds also kept an eye on the light on the USB stick I had attached. No light.
- The USB stick was attached because i tried a BIOS recovery, and the .ROM file was on the USB. But it failed due to the USB not becoming active.
- Took apart the laptop, took out the mobo, and measured the pins where the AC jack should lead power to. The mobo receives 19,38 V.
- With mobo stand alone in front of me (only the cable to the on/off button is connected), plugged it into the AC. White light indicating it is getting power comes on. When I tap the on button, same thing happens. Second light + power button light comes on for a few seconds, than is gone again.
- Fan is dustfree, radiator fins are as clean as they come (laptop has only been used a couple of times, then it sat in a drawer for two years)
- No visual problems on the mobo (discoloration, no funky smells, ...)
I am running out of ideas. What else can i try/test to identify the problem. Other than getting my hands on the electronic lay-out of the mobo and testing all components on it. The motherboard is a PFKAA LA-8391P (rev 1.0) form vendor Hannstar.
I just don't get why the mobo is failing. It hasn't been used that much, so a fried mobo, I don't think so. Do they build these things with an internal timer that says "time to fail"?? I have many laptops that are over 10 years old. They all work (Toshiba, Dell, HP, Fujitsu). And my most recent and most powerfull machine is failing without ever being used to full capacity!!
It cost a lot, I need it at this point, so I would like to get it to power up again. Any ideas??
Thanks in advance for any help
V.
My Toshiba satellite P855-34Q was bought in 2015. I used it for a couple of weeks, but then got a laptop from work. The Toshiba has been kept since then in a drawer in my living room. Dry, no temperature swings, dust free. Same place where I keep my work laptop and where my husband keeps his 10 year old Toshiba. This week, I needed it for some virtualization (which my laptop from work nor my husband's laptop is good for, not enough RAM)
Took it out, put the battery in, plugged the AC in and connected it to the power net. I got an orange charging light.
I tapped the power button: White light in the power button, white light on the front panel (next to the charging light). But after only two or three seconds, the light on the power button and on the front, goes out again. Nothing appears on the screen, no beeps, no sounds of fan or hard drive.
This same behaviour is still present after I tried the following steps:
- Measured the voltage on my CMOS battery. It was only 2,14V, so too low. When the laptop is charging though, the voltage on the CMOS battery climbs tot 2,68V.
- Left it to charge until the charging light was white, indicating fully charged. Turned it on, same behaviour.
- Took the battery out and measured its output. Normal output voltage
- Measured the output on the AC adapter. I measure a voltage of 19,38 Volts, so normal.
- Without battery, only connected through the AC adapter, tried turning it on. Same behaviour.
- Without the battery, and without AC feed, I held down the power button for over a minute to discharge anything residual. Plugged in the AC, turned it on, same behaviour.
- Same thing as the previous step, now with only the battery. No success.
- Took out the hard drive, tried turning it on. Same thing happens, power light goes out again after three seconds (AC and battery tried separately)
- Took out one RAM stick, tried again, took out second RAM stick, tried again, swapped each RAM stick to another bay, tried again (again, as well with AC only as with battery only).
- Put another CMOS battery in parallel over the drained one to get 3V. No success.
- Measured if there was a drop in CMOS battery output voltage when turning the laptop on: no drop in voltage.
- During the three seconds when the "on" lights are actually on, tried to open the CD drive, nothing happens.
- During these three seconds also kept an eye on the light on the USB stick I had attached. No light.
- The USB stick was attached because i tried a BIOS recovery, and the .ROM file was on the USB. But it failed due to the USB not becoming active.
- Took apart the laptop, took out the mobo, and measured the pins where the AC jack should lead power to. The mobo receives 19,38 V.
- With mobo stand alone in front of me (only the cable to the on/off button is connected), plugged it into the AC. White light indicating it is getting power comes on. When I tap the on button, same thing happens. Second light + power button light comes on for a few seconds, than is gone again.
- Fan is dustfree, radiator fins are as clean as they come (laptop has only been used a couple of times, then it sat in a drawer for two years)
- No visual problems on the mobo (discoloration, no funky smells, ...)
I am running out of ideas. What else can i try/test to identify the problem. Other than getting my hands on the electronic lay-out of the mobo and testing all components on it. The motherboard is a PFKAA LA-8391P (rev 1.0) form vendor Hannstar.
I just don't get why the mobo is failing. It hasn't been used that much, so a fried mobo, I don't think so. Do they build these things with an internal timer that says "time to fail"?? I have many laptops that are over 10 years old. They all work (Toshiba, Dell, HP, Fujitsu). And my most recent and most powerfull machine is failing without ever being used to full capacity!!
It cost a lot, I need it at this point, so I would like to get it to power up again. Any ideas??
Thanks in advance for any help
V.
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