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M5126 help! I am stupid
Posted by: glay78 on 2020-11-17 03:34:04
Ok long story short, I connected the battery in wrong polarity, after I found out I was wrong I switched back. 
 

The portable still powers up but unable to run scsi HDD nor charge the battery. I think one mosfet could be blew but I’m not sure which. When I plugged in adapter and battery, voltage tested at battery point was 6.33v. If I do this on a working M5120 it reads 6.9v so I’m presuming the power couldn’t charge the battery hence not giving enough power to run the scsi HDD too.

Can anyone enlighten me which mosfet or which component is affected?
Posted by: 360alaska on 2020-11-17 06:46:11
An expensive mistake, Did you check the fuse? 
 

Then, you’ll need to check the mosfets: https://www.utm.edu/staff/leeb/mostest.htm
Posted by: glay78 on 2020-11-17 06:47:00
An expensive mistake, Did you check the fuse? 
Is there a fuse on the board?
Posted by: 360alaska on 2020-11-17 06:49:11
Near the battery power connector.
Posted by: glay78 on 2020-11-17 06:50:23
Near the battery power connector.
F1? 
Posted by: 360alaska on 2020-11-17 19:11:52
Yeah F1 = Fuse 1
Posted by: glay78 on 2020-11-17 19:23:45
Yeah F1 = Fuse 1
My F1 is a resistor not a fuse. 
Posted by: 360alaska on 2020-11-17 19:28:57
Whats the resistance? Should be near 0.
Posted by: glay78 on 2020-11-17 19:32:00
Whats the resistance?


EED10627-D724-4167-A5A8-150D6C8A3D16.jpeg
Posted by: 360alaska on 2020-11-17 19:33:47
That's probably a fuseable resistor, did you check it with your meter?
Posted by: glay78 on 2020-11-17 19:35:49
That's probably a fuseable resistor, did you check it with your meter?
It’s not shorted. 
Posted by: LaPorta on 2020-11-17 20:10:55
One thing for certain: the battery runs literally everything. The adapter simply charges the battery. If the SCSI, etc is not working, it isn’t a lack of pure power.
Posted by: glay78 on 2020-11-17 20:43:37
One thing for certain: the battery runs literally everything. The adapter simply charges the battery. If the SCSI, etc is not working, it isn’t a lack of pure power.
Currently what I assessed is with power adapter I can’t get the battery charged 
Posted by: Bolle on 2020-11-17 21:45:36
It’s not shorted
It’s blown then. You’ll have to replace it.
Posted by: glay78 on 2020-11-17 22:21:27
It’s blown then. You’ll have to replace it.
let me test the Ohms later, it should be 23Ohms if I’m not wrong
Posted by: 360alaska on 2020-11-17 22:40:21
21 ohms.
Posted by: Bolle on 2020-11-17 22:51:33
It's supposed to have 0 Ohms as it's a fuse and not a resistor.

Violet - Black - Red edit: actually that's probably orange which would make more sense -> means it's a 7A fuse.

If it's open or anything greater than 0 Ohms in resistance then it's going to be defective.
Posted by: glay78 on 2020-11-17 23:54:48
It's supposed to have 0 Ohms as it's a fuse and not a resistor.

Violet - Black - Red edit: actually that's probably orange which would make more sense -> means it's a 7A fuse.

If it's open or anything greater than 0 Ohms in resistance then it's going to be defective.
I checked continuity, it’s open. 
I checked for ohms and it shows 1, as the default is already showing 1
Posted by: glay78 on 2020-11-18 03:18:47
@360alaska @Bolle

thanks guys! I changed F1 and it works now!!!
Posted by: Plottem on 2023-01-19 03:04:14
Good morning, time has passed since this thread but I find myself with the problem that I can't find a spare part for this F1 its fuse resistance?, would you be so kind as to tell me where I can buy it or the values to look for it? All the best
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