I bought a Hawk E-Z Tune Diagnostic Analyser. The pointer does not move, so I figured the battery was dead. When I opened it, I found 2 battery holders: 1 for a 9v battery and another that seems to be for 2 separate AA batteries (I had 4 wires coming off of it). Problem is, there isn't room in the thing for both a 9v and the 2 AA batteries. I think someone has messed with the internals. Anyone have one of these? Should it only have the 9v battery? Anyone able to get me a shot of the back with the cover off?