Test 46, Check VBAT Open To Coil
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 1991 Ford Ranger, 1991 Ford RV Cutaway, 1991 Ford Pickup, 1991 Ford F-Super Duty, and 1991 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
Turn key off, and connect ECA. Connect EDIS Diagnostic Cable (007-00059) to breakout box (T83L-50-EEC-IV), EDIS module and coil pack. DO NOT connect VR sensor tee. See Figure. Use EDIS No. 6 overlay. Connect EDIS diagnostic cable negative to negative battery terminal, leaving positive lead disconnected. Set EDIS diagnostic cable box switch to 4/6 CYLINDER position. Set DVOM to 20-volt scale.
Turn key on, but leave engine off. Measure voltage between breakout box pins No. (+) J5 (VBAT C) and (-) J7 (BAT -). If voltage is greater than 10.5 volts, go to next test. If voltage is less than 10.5 volts, repair open circuit. Remove all test equipment, and reconnect all components. Clear Continuous Memory, and check for fault codes.