Test S: Step 3
3) Power to MAP/BP Sensor If vehicle is not equipped with a MAP/BP sensor, go directly to step 8). Use Ford Motor Co. MAP/BP tester for this test. If Green light is on, VREF circuit voltage is okay. If Red light (or no light) is on, VREF circuit voltage is too low or too high. Turn key off and disconnect MAP/BP sensor from vehicle harness. Connect MAP/BP tester between vehicle harness and MAP/BP sensor. Connect banana plugs of tester into DVOM and set DVOM on 20-volt scale. With tester connected, turn key on. If Green light is on, go to next step. If light is not on, repair open in VREF circuit, remove MAP/BP tester. Reconnect components and retest symptom.