my yukon is a flex fuel model. I had to replace the fuel pump a while back and the mechanic installed the wrong pump. Anyway the deal is that the plug that was on the other pump was labeled A B C D and was side by side and also color coded. The plug I have now is labeled 1 2 3 4 and is square and all the wires are white. the plug itself fits around the outside of the plug on the fuel pump. Not the one that snaps into the plug I know one has to be a voltage source 12v (?) one would be ground and I believe the other two go the fuel gage. Whats the cross reference?
fuel pump pigtail wiring from long plug to square plug. on 2002 GMC Yukon
changing the plug is the norm,the new plug wont overheat like the orig. due to cont.getting loose over time. I my have one at my shop ill ck. when i get there,but iv had very bad luck with the cheap pumps that come with the white wire set up they almost always fail in the first year. If you buy a better brand pump they come with the purple,gray,black,black&white or orange wires on them and all you have to do is match them up. if you post what col. you have on the truck harn. ill let you konw what they are.