Be sure all power is off the circuit before making any resistance measurements. Do not touch the metal probe ends while making resistance measurements. It will cause inaccurate measurements. The tan/lt green provides the ground for the relay coil. Remove the relay and disconnect the computer wiring harness. Make sure you have removed the test jumper. Measure the resistance between a good ground and the tan/lt green wire: you should see an infinite open circuit. If not, you have short to ground or bad insulation somewhere on the tan/lt green wire. Put one test probe on the tan/lt green wire connector on the fuel pump relay socket and the other on the tan/lt green wire connector on the computer wiring harness (pin 27), you should see less than 1 ohm. An infinite open circuit or reading in excess of 1 ohm means a dirty connection or broken wire.