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Home >> Ford >> 2003 >> Mustang Base, 2D Convertible, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 19 (Charging System - Generators & Regulators) >> System Tests >> Test C: System Overcharges (Greater Than 15.5 Volts)
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Test C: System Overcharges (Greater Than 15.5 Volts)

WARNING: This page is about a different car, the 2002 Lincoln Navigator, 2002 Lincoln Blackwood, 2002 Ford Pickup, and 2002 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
  1. Disconnect generator 3-pin harness connector. Turn ignition on. Measure voltage between generator terminal "A" (Orange/Light Blue) and positive battery terminal. If voltage is less than .5 volt, go to next step. If voltage is .5 volt or more, repair high resistance in circuit between generator and battery.
  2. Turn ignition off. Inspect generator and regulator grounds (mounting surfaces and fasteners). Inspect battery ground. If problem exists, repair as necessary. On Lightning models, if all grounds are okay, replace generator. See GENERATOR  under REMOVAL & INSTALLATION. On all other models, if all grounds are okay, replace voltage regulator. See VOLTAGE REGULATOR  under REMOVAL & INSTALLATION.