Dlc doest connect

[highwindco]

Ok here's the story. I've bought the truck it's a 97 f250 automatic 5spd and It runs really good I just can't hook my scanner up to it. I've checked all fuses all good. The scanner does have power at the port because the backlght turns on as soon as I plug it in. But it keeps telling me to check connections. I know pin 4 and 5 are ground and they do in fact have good ground and also I know pin 16 is power and I hav a good 12.5v there. I'm afraid to mess with the data+ and data- along with the PCM input plug. But if anyone else has any ideas gimme a shout. I've thought bad wireing could be a problem but I seriously doubt it. The truck actually looks brand new inside and out and very well taken care of.