PCB 903-1598 controlls the gas pressure valves for GaSonics L3510 chamber during the End Of Process (EOP).  This board is known to fail, causing deficient to zero throttle valve control during EOP.  If you’re experiencing these or similar symptoms, contact GetSpares.com for replacement/repair solutions.  GetSpares maintains fully operational L3510 tools, which means fully operational test environments for all relevant parts.  Rest assured that the part you receive from GetSpares will be fully functional.

GaSonics L3510 EOP Pressure Controller 903-1598 PCB