First, My son-in-law's truck is a 2006 1500 Silverado, V-8. His check engine light is on, but the truck is running fine. I hooked my scanner up to it and it did not power up. I check the scanner by hooking it up to my 2004 Tahoe and it came right on. Is there a possible fuse blow in his truck that powers up the scanner? I have briefly looked over the wiring diagram in the Haynes manual, but have not located the area where the scan tool is hooked up. How would it be labled in the wiring diagram?
Thanks Jerry

 

Is there any visible pins on the plugs that may have been pushed back?

 

I will look next time I see the truck. Son-in-law said someone else tried to scan the truck at an earlier date and he appeared to not know what he was doing, so there maybe a pin messed up.

 

I would not rule out a fuse either, never hurts to check them.

 

OBD1 you used to short a couple of pins out in the diagnostic connector to read the codes manually, but OBD2 doesn't work that way so for sure check the pins, and if they did try it, its very possible to have shorted it out and blown a fuse...

 

I have read else where on the internet, where the power supply for the OBD-II is the same fuse as the cigarette lighter. Also by looking at the wiring diagram a few minutes ago I found it. Thanks for the help.

 

sweet yeah I just verified in my book that pin 16 on the DLC is the battery power to the connector and probably the power to your scanner / code reader.