I'm not sure if this is correct, the output pin 7 is grounded or the ic has a short. I'm just trying to rule it out. https://www.ti.com/product/LM2574?qgpn=lm2574
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Hello everyone. 😀
As per thread title, this unit has a serious SMPSU fault. It blows F1001, which is a 10A M205 in the phase from the mains input.
Very first thing I tried, was simply replacing the fuse, but the replacement ceramic fuse blew immediately.
Looking at the schematic for this PSU, I then removed what I thought was the next likely candidate: D1001 - the HV main bridge rectifier.
This isolated the fault(no longer blows the main fuse), but does not point me to the actual fault.
There are no devices that have exploded or otherwise show signs... -
- Prior owner tried a replacement main board. No difference.
- Samsung 2x red blinking standby LED = panel fault
- Jumpered FB_TRDY_1 (pin 1 CN1300 left. main tcon->left side buffer boards) and FB_TRDY_3 (pin 95 CN1301 right. main tcon->right side buffer boards) This allows testing individual T-Con (on main board) connection to panel on this Samsung. Found fault on left side (viewing from rear of TV)
- Each side has 2 buffer boards, disconnected left side flex between 2 buffer boards. Fault is on the left most board.
- Tape masking eventually isolated to CN1300 pin 15 (CKV4_GOA) Display
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I have been having a fun time at work with two pieces of equipment that had shorted components or shorted component cables to machine frame
I would check what my multi meter was telling me about how many ohms I getting with the multi meter was telling versus the ESR was telling me about weather or not it really was a short to machine ground or not
One note at first we thought that it might be a bad I/O card or a malfunction PLC including me as well but I thought I would try and see if removing the I/O cables would make a difference or not and this time it did make a difference... -
Hello,
I have a strange fault with a Lenovo ThinkPad E14 G2 (Board No. NM-D011 Rev. 1.0).
The first Problem, which I fixed already, was a dead TPS65944AD (USB Type-C) controller. After I fixed this fault, all functions working fine and the notebook run very well with the charger and battery.
On the next day, I tied to start the notebook with the battery, but nothing happened. I started with the charger and on windows, I saw, that the battery was empty. And this was nearly impossible, because the battery was charged. I disconnected the battery and found out, that the board... -
Hi all
I bought this Dremel several years ago (8220 + 880 2.0Ah battery). After about a dozen light uses it developed a power fault. I asked Toolstation to start a warranty claim for me and they just refunded me in full without asking for it back instead. Would be nice to fix it instead of consigning to the dustbin.
It is complete luck of the drawer whether it powers on or not. Sometimes it will be completely dead, no lights no response. Switching power on and off repeatedly and/or removing and reinserting the battery will eventually make it spring to life. After that...
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