Do you get same reading on any big coil???
I just tested one 01521 and got 0.494/3.000 at C7056.
I just tested one 01521 and got 0.494/3.000 at C7056.
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820-01521 no power
- Thread starter Paky46
- Start date
"Do you get same reading on any big coil???"
I gave refference values from similar board.
You have a problem on PPBUS_G3H.
I gave refference values from similar board.
You have a problem on PPBUS_G3H.
Check diode mode to ground on all coils.
See if any gets same readings as in PPBUS_G3H.
See if any gets same readings as in PPBUS_G3H.
"Same", in both directions?
Please post accurate information.
Check in diode mode between PPBUS_G3H and L8100.
Please post accurate information.
Check in diode mode between PPBUS_G3H and L8100.
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So the problem is not Q8100.
No other coil gives similar readings to ground as PPBUS_G3H for sure?
No other coil gives similar readings to ground as PPBUS_G3H for sure?
Something connected to PPBUS_G3H affects diode mode reading.
As my mentioned readings, you see that reverse way may be very high, going to OL even (more than 3.000).
And direct reading is also higher than your (almost 0.500).
Check/replace Q7030/40.
As my mentioned readings, you see that reverse way may be very high, going to OL even (more than 3.000).
And direct reading is also higher than your (almost 0.500).
Check/replace Q7030/40.
If is same board model, should be equivalent; don't you think so?
When in doubt, compare datasheet...
When in doubt, compare datasheet...
Post again diode mode reading at PPBUS_G3H...
Still bad.
Remember to check both ways there, when in doubts.
So you have a damaged component connected to PPBUS_G3H.
Not easy to find, if is not coming from a secondary power supply.
If you are VERY SURE no coil gets same reading, you can try injecting voltage into PPBUS_G3H.
Just in case, start with 1V and use IR cam to inspect entire board (both sides).
You can go up (slowly) until 15V and may have luck to detect the culprit.
Probably no big temp difference between components, that's the reason you need IR camera.
Be aware, if you have short between PPBUS_G3H and a secondary coil (which you forgot to check), board can be letally damaged!!!
Remember to check both ways there, when in doubts.
So you have a damaged component connected to PPBUS_G3H.
Not easy to find, if is not coming from a secondary power supply.
If you are VERY SURE no coil gets same reading, you can try injecting voltage into PPBUS_G3H.
Just in case, start with 1V and use IR cam to inspect entire board (both sides).
You can go up (slowly) until 15V and may have luck to detect the culprit.
Probably no big temp difference between components, that's the reason you need IR camera.
Be aware, if you have short between PPBUS_G3H and a secondary coil (which you forgot to check), board can be letally damaged!!!
"c7414 shorted"
Shorted no; you had high readings there, but not expected.
Not always, only short is bad!
That's the reason to take notes about correct readings, from good boards; in several test points.
Tested external video?
Try also disconnecting internal LCD.
Check for USB activity.
What is L7210 voltage after 10-15s?
Shorted no; you had high readings there, but not expected.
Not always, only short is bad!
That's the reason to take notes about correct readings, from good boards; in several test points.
Tested external video?
Try also disconnecting internal LCD.
Check for USB activity.
What is L7210 voltage after 10-15s?