Yesterday there was some work done on the PSL racks, specifically to the AA chassis. Once this work was complete (PSL offline for ~16 hours) the NPRO recovered automatically, but no light was making it to the PMC.
I went into the diode room and found that the flow sensor was tripped. I added water to the crystal chiller and reset the flow sensor. Then I opened the HPO external shutter and the PMC was able to lock successfully..
There is currently still an out-of-range warning on the long range actuator, which I do not understand. I thought the LRA was inside the HPO which is offline, but normally the LRA indicator in the sysstat window is not in a warning state.