I used it in August and it worked fine for me. No coupon needed. I leave next Thursday and have my car reserved through them again using the entertain code.
Have you tried using any of the other codes found at mousesavers.com? I have a full size car reserved at Dollar from Sept 22-29 at a rate of $126 per week using the FISH code. Keep looking every day and trying different codes. I got the rate lowered 3 times after I checked back several times.