Charging Without Load

1. Prepare the tester:

• Rotate the Load Increase control to OFF,

• Check each meter's mechanical zero. Adjust, if necessary.

• Connect the tester Load Leads to the battery terminals; RED to positive, BLACK to negative.

• Set Test Selector to #2 CHARGING.

• Adjust ammeter to read ZERO using the electrical Zero Adjust control.

• Connect the clamp-on Amps Pickup around the battery ground (-) cables.

2. Turn the ignition switch to "ON" (engine not running) and read the amount of discharge on the ammeter. This is a base reading for current the alternator must supply for ignition and accessories before it can provide current to charge the battery.

NOTE: The reading should be about six amps.

3. Start the engine and adjust the speed to about 2000 rpm. Some models may require a different speed setting.

4. After about 3-4 minutes, read the ammeter and voltmeter. Add this ammeter reading and the reading found in step 2 (engine not running).

NOTE: The total current should be less than 10 amps. If it is more, the alternator may still be charging the battery. Once the battery is fully charged, you should get specified results.

The voltage should be within the specs for the alternator. This is usually between 13 and 15 volts. Refer to the appropriate repair manual. If the voltage is more than specified, replace the regulator. If the voltage is less than specified, ground the alternator field terminal "F" and check the voltmeter reading. This bypasses the regulator, so do not exceed the specified test speed. If the reading is still less than specified, check the alternator.

5. Remove ground from terminal "F."

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

Don't pay hundreds of dollars to find out what is wrong with your car. This book is dedicated to helping the do it yourself home and independent technician understand and use OBD-II technology to diagnose and repair their own vehicles.

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