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M31 RV is a red transient that erupted in 1988 in the Andromeda bulge,reaching a luminosity intermediate between novae and supernovae. It was coolthroughout its outburst, unlike a normal classical nova.  In 2006, Bond & Siegel examined archival HST optical images of the M31 RVsite, obtained in 1999. We found only old red giants at the site, and no starsof unusual color. However, Shara et al. recently claimed to have detected (a) abright UV source within the error box in HST UV images taken in 1995, (b) a hot(Teff>40,000 K) optical source in the same 1999 images that we examined, and(c) cooling of this source from 1999 to 2008. Shara et al. argue that thissource's behavior is consistent with a classical-nova outburst occurring on alow-mass white dwarf.  I have re-examined all of the HST frames, including new ones obtained in2009-2010. I find that: (a) the bright 1995 UV source reported by Shara et al.was actually due to cosmic rays striking the same pixel in two successiveexposures; (b) the claim that an optically bright star in the error box is veryhot is actually due to misinterpretation of red-giant colors in the STmagnitudesystem; (c) there is no evidence for variability of any source within the errorbox from 1999 to 2010; and (d) there are no stars of unusually blue or redcolor in the error box. Our 2006 conclusions remain valid: either M31 RV hadfaded below HST detectability by 1999, or its remnant is an unresolvedcompanion of a red giant in the field, or the remnant is one of the red giants.

Hubble Space Telescope Imaging of the Outburst Site of M31 RV. II. No Blue Remnant in Quiescence