To clarify what I earlier ask. The question is, what would cause the tester that Autozone hooked up not to work correctly. The situation was that the tester was hooked up correctly and it was confirmed that the tester works but when hooked up to my suburban it kept saying that it needed to be hooked up, therefore it was not getting a signal from my car. So what would keep my suburban from giving the correct signal to the tester. We checked for blown fuses in my fuse box but apparently there is still no power at the plug in site. Please someone help, suburban is running very rough and seems to not be hitting on all cylinders
