Re: Help with LKP-0P023 REV0.3 PSU

Sure enough by bypassing the PFC, this one appears to work ! Q5 is dead though, and I found R53 was open so I suspect the PFC chip has bought it as well (just didn't blow its top off)

If anyone wants to try bypassing the PFC to see if the rest of the supply works, do the following:

Remove R57, Q5, L2, D1
Remove R22 (might not be needed, but best to keep the PFC out of it if the chips still there)
Fit wire links at J3 and D2

Oh, and fit a new F1 and E2 - this is usually why the PFC exploded...

Re: Help with LKP-0P023 REV0.3 PSU

About to do one of these myself.. the 68uF 450V primary cap was bad, F1 and R57 are gone, not sure about Q5. IC1 seems to have survived (at least the top hasnt blown off of it!)

I'll be checking the rest of the supply works first - i have a 100uF 450V capacitor, and this first stage is a PFC so it can be bypassed. If the rest of the PSU is shot, there isn't much point in attempting a repair I think.

I wish they'd build protection into PFC controllers so that if the cap fails, they dont just drive the MOSFET on hard,...