The three failed T2 cooling system secondary side solenoid valves were tested yesterday to try to determine the problem.  The test steps are detailed below:

• New spare valve (NSV) produced audible "click" and valve was seen to physically open when 24V DC driving voltage was applied
• Failed valves of July 25, 2017 (J25), July 10, 2017 (J10), and November 2016 (N16) all did not click or open when driven
• The solenoid of NSV was removed from its valve and installed on each of the failed valves in turn.  The NSV solenoid succesfully opened each of J25, J10, and N16 (the valve bodies and pistons of the failed valves appear to be fine, and the solenoids all faulty)
• Each solenoid's coil resistance was measured: NSV = 187kOhm, J25 = 200kOhm, J10 = O/C, N16 = O/C

On the next maintenance day Tony Tateyama is planning on performing continuity tests on the T2CS:SVSEC control cable and comparing it to the control cable for identical solenoids in the system.