Jeff and I have been noticing an SDF diff going into observing where the input of the PR3 M1 LOCK P and Y filter banks is turned ON. However, there is no ISC signal ever sent to PR3, so there is no reason for this to get turned on. We have been SDFing it OFF, thinking that it was turned on due to some error in the PR3 estimator testing. But we learned today, when we had an observe diff in the PR3 model again, that actually the guardian is turning it on. I found that the input is turned on in PREP_ASC_FOR_FULL_IFO, which I think is some holdover to some PR3 wire heating correction, at least according to a variety of comments in the guardian code. So, to avoid this continuing to be an issue, I commented out lines 3397 and 3398 in ISC_LOCK, which will ensure the input will stay OFF, which we are SDFed as. We are not correcting PR3 wire heating at this time.

When I made these corrections, I pulled us out of observing momentarily to load the guardian, which I felt was a necessary task to prevent confusion and possible OWL shift operators being woken up by SDF diffs preventing observing.