Under Dash Data Port

TyeeMan · August 23, 2010

Hi,

2002 GMC 1500 HD, 6.0L 4WD, Auto trans.

I'm trying to scan for any codes that might be in the computer (my torque converter is cycling) I've tried a couple of different code readers and neither of them connect electronically. I either get a message that says cannot connect, or in the case of the last code reader I used it's supposed to power up as soon as you plug it in, it does not.

Soooo am I in deep weeds here? If I can't get the code reader to "connect" will the dealer be able to get their scan tool to read anything?

When I connected the code readers to my Suburban they fired right up, no problem. I looked at the pin locations on the under dash data port on my 1500 HD and they mach the pin locations on my Suburban.

What gives? Help! Any info would be greatly appreciated.

rmck490 · August 23, 2010

Power to the DLC is usually shared on the cig lighter circuit. Check the fuse.

[email protected] · August 23, 2010

Power to the DLC is usually shared on the cig lighter circuit. Check the fuse.

True this, CIG LTR fuse in the underhood electrical center. May just be CIG, though.

TyeeMan · August 23, 2010

Ahh, ya know that might just be it. Ya know you have the 3 power ports (2 power ports & 1 cig lighter) in the center of the dash, , well one of th power ports is dead and two work. Is there one fuse for each of those power ports or are they all grouped into one fuse? If they all run off of one fuse I might have a another problem.

By the way the power port that is dead is the far right one as you sit in the drivers seat. Any chance that's the one that powers the DLC?

Thanks!!

[email protected] · August 23, 2010

Ahh, ya know that might just be it. Ya know you have the 3 power ports (2 power ports & 1 cig lighter) in the center of the dash, , well one of th power ports is dead and two work. Is there one fuse for each of those power ports or are they all grouped into one fuse? If they all run off of one fuse I might have a another problem.
By the way the power port that is dead is the far right one as you sit in the drivers seat. Any chance that's the one that powers the DLC?

Thanks!!

The one that looks different inside is the cig lighter. The other two are just aux power ports and run off a different fuse. And, yes the cig lighter is the farthest right one.