Soltron Electronic III Display PCB Voltage Regulator Replacement

This ia a Soltron Electronic III Display PCB from an Ergoline Soltron Chill XL70 Tanning Bed. This board has obvious thermal defects to the L5973D voltage regulator IC as well as to the trace and the board. It is rumored that this particular board is plagued with this particular issue. The entire board new is likely $800~$1000 and used ones can go for $400~700.

Here is some imagery of the affected component:

These ICs are surface mount and are soldered on the underside. Without a decent hot air soldering station, flux, solder paste, etc… you could botch the repair.

Since the original chip was toast anyway, i poured the heat to it with a touch of flux and removed it. It takes patience (as well magnification in my case) but it’s not too bad, you just have to be careful not to overheat any surrounding components, etc…

Then i cleaned up the pads and traces (except for the one that was not a charred crevasse in the board), applied solder paste to the clean pads, then a touch of flux and the chip settled into place (after 5 solid minutes of nudging and shifting and heating). Once it was tacked into place a made sure i had good flow everywhere, then used a single strand of some 14~12 AWG stranded and made a good repair between the leg of the IC and the pad.

Here is the 1st try. It probably would have been okay… but I reworked those areas.

Here is it again after rework:

This board will be field tested and I will update this as needed.

UPDATE: That did not fix the board. Back to board-level diag… We will keep you posted.