Test Aa: Step 2
2) Check VREF Signal at TPS Ensure fuel pump inertia switch is set (button pushed in). Turn key off and wait 10 seconds. Set DVOM on 20-volt scale and disconnect Throttle Position Sensor (TPS). Turn key on, leaving engine off (KOEO). Measure voltage at TPS harness connector between (VREF) and SIG RTN. If reading is less than 4 volts or more than 6 volts, go to TEST C, step 1). If reading is between 4 and 6 volts, reconnect TPS and go to next step.