Possible solution to Teclast failure to charge / start problem: theory

[Max]

I have had a Telclast F7 laptop for about 3-4 years.

I recently have come to question whether the spec of 12V2A might actually be 12V/3.42A, and this difference in amperage is causing the laptops to eventually stop starting up.

The specifications for the charger are listed as 12V and 2A; after the 1st original AC adapter died, I bought an AC adapter 12V and 3 Amps.  And, that did okay until recently when it shutdown with a first time “ slide to close message” and wouldn’t start up.
Or, rather, the occasional cloying blue LED light , and sometimes a half hearted attempt before nothing”.

Checked the AC adapter plug which showed it was putting out 12V. Opened the case, reset the SSD, unplugged & replugged battery ( not swollen , but only had my voltmeter pen , not volitmeter to check out power Jack and battery ). Shot air to clear out any dust. Cleaned all contacts – plug, Jack etc .

Got two eventually restarts where was able to check there wasn’t any weird W10 settings for “slide to close” issue. Keyboard inputs were screwy , each time different, when I uninstalled drivers and reset. Also uninstalled ac adapter and power management drivers, shut down, did unplug – replug of battery and tried to restart…. same lame half-hearted fail reoccurred. It was late so left it.

Later today, will get a 12V adapter but this time with 5 Amps. Why?

First, while undervolting or overvolting can cause problems, there isn’t anything problematic about “over amping” – the device will just take what it needs” . Under amping however can cause problems – in most cases, overheating the adapter ( not pc) but also might be the cause of weak unsuccessful startups.

Yes, the Teclast company ( and I double checked ) claim the F7 is spec’d for 12 Volts and 2 Amps. However, I noticed some sites have listed the spec as 12 Volts and 3.42 Amps ( I was using 3 Amps , so close but no cigar ). And, to my mind, that makes more sense … 41 Watts versus 24 Watts ( 12V/2A).

Will know whether that a 12V/5A will prove to be the solution in a few hours.

If I’m right, then this could be the reason why so many Teclasts ( and similarly EZBooks etc) seem to fall afoul of the “ tiny blue LED but not able to restart “ problem — the actual spec w/r Amperage is understated ( whether on purpose or incompetence, I don’t know).

[Max]

FYI I got the F7 back up.

However, it wasnt so straightforward.

The new 12V 5A adapter didnt do much at first.

I tried a number of things and gave up.

On a hunch, I left it plugged in for a few hours with an adapter set at 9V with a 3A max capacity. The thought was that undervoltage would then draw in extra amps / current to make up the difference. And, then just on battery, it worked. After that, I used the 12V 5A adapter.

The only remaining problem is that the keyboard is screwed up. I can type only some keys but others are totally screwed. Backspace button yields 7, and pressing certain keys gives a bunch of extra ones. Tried resetting registry for keyboard , regedit … changed language preferences, uninstalled keyboard drivers and made sure it didnt have game mode on. Currently using a bluetooth keyboard from my iPad. Its a W10 problem so last option is to backup and reinstall W10. Dont think its a keyboard problem but if someone could tell me how to unplug and reset the keyboard connector inside [or whether its easy to do ], Id be grateful.

And, one more problem …. the SLIDE TO CLOSE MESSAGE came up again |after hours of ZOOM, so it probably got overheated ] and the thing shutdown. However this time, I could restart it no problem. The keyboard remains dynsfunctional however.

 

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