i own an 02 silverado 2500 the service engine light soon has been lit for several weeks now i finally got around to hooking my scan tool up to pull codes well i plugged the scanner in and nothing happened no power was coming from the vehicle connecter i tested my scanner on another vehicle to confirm it was working and it was.now i need some help troubleshooting the faulty obd II port on the truck

Does the cigarette lighter work? The OBD-II port shares the same fuse.

//2000CAYukon

well i have 3 12v outlets 2 of them work all fuses are good

http://www.troublecodes.net/OBD2/

Check for ground on pin 4-5
Check for 12 volt battery power on pin 16

When my obd11 port was dead, so was the lighter socket.
It was the fuse.
Meter the fuse or swap it. They might look good but be bad
Bob B

Meter the fuse or swap it. They might look good but be bad

:iagree:

I'd bet the one lighter that doesn't work shares power with the DLC. Either a fuse or an open wire. If you don't care about keeping the wiring factory, just cut the power wire a few inches away from the connector (to leave room to re-connect if you ever decide to fix it) and run a jumper wire from it to the battery or another lighter when you want to check codes. It doesn't go to any computers at all, it just provides power for a scan tool.