1999 Ford Taurus

1. Disconnect generator 3-pin connector. With ignition on, engine off, measure voltage drop in circuit "A" by connecting voltmeter positive probe to generator 3-pin connector terminal "A" (Orange/Light Blue wire). Connect voltmeter negative probe to positive battery terminal. If voltage is less than.25 volt, go to next step. If voltage is.25 volt or greater, check fuses and circuit between battery and generator connector terminal "A". Repair as necessary. See WIRING DIAGRAMS. 2. Reconnect generator 3-pin connector. Backprobe 3-pin connector terminal "I" (Light Green/Red wire) with voltmeter positive probe. Connect voltmeter negative probe to ground. If voltage is greater than one volt, go to next step. If voltage is one volt or less, repair high resistance in Light Green/Red wire between generator and instrument cluster. See WIRING DIAGRAMS. 3. Inspect ground connections between battery and engine. Ensure generator mounting surfaces are clean and bolts are secure. On 3.0L 2-valve engines, also ensure voltage regulator mounting surfaces are clean and screws are secure. On all models, if all grounds or mounting surfaces are not okay, repair as necessary and check system operation. If grounds and mounting are okay, replace generator and check system operation. See GENERATOR under REMOVAL & INSTALLATION.

Check fuse 26 battery junction box

If battery boils, it s overcharging, test it with a voltmeter if it's higher than 13-15 volts at 2000 rpm, test as shown above.