Not sure how you was getting the temp readings, but if you was reading 170 outside the case it was probably way over that for actual temp. Still should not have failed for that reason though. I would guess the overstressed batteries were more the factor then anything else. Send it in and I'll figure out what failed on it and get you fixed back up.
take a look...see the oil droplets on the cover and the inside of the case has like a sandy gritty substance...you can see it good on the wires where they run out the case