Just tried mine out this weekend, I am having starting trouble with my wifes jeep. I was able to use the power probe to put power to the starter fuse and it would throw the solenoid but not the turn the starter, the same as the key was doing but easier to see under the hood. Looks like starter time. I can see this being very helpful. I will pay for a good tool and this thing looks to be a awesome one. Now i just need to know what else i can do with it.