I want to know if there has been any work done on brand equity loss from marketer and consumer perspective as i am coordinating a work group, qualitative research, on it at PhD level.
There are members of ResearchGate who have written extensively about this topic. It might be worth looking at their publication pages or contacting them:
Elena Delgado-Ballester https://www.researchgate.net/profile/Elena_Ballester/publications
Con Korkofingas https://www.researchgate.net/publication/233187679_Product_recall_brand_equity_and_future_choice
Here you can find a lot of brand equity cases in customer equity builiding context. They are good for students, but I am not sure, if the book is aviable now to buy. If not, try library