1996 Chevrolet Suburban Power door locks

At which ever door you want to check, check voltage and ground for that door. On the hinge side of door, should be wiring harness, may have a rubber boot protective covering. Pull the covering back to expose the wiring. For the unlock position, tan wire is voltage, gray wire is ground. Check voltage and ground both. You could use a testlite between the tan wire and gray wire, with the switch activated, If the lite comes on, you voltage and ground. Could be problem with switch or relay?