Removal & Installation - Ford Ranger Maintaince And Repair Manual

Battery Load Test
1. With the engine running, turn the air conditioner ON (if equipped) or the blower motor on high speed
and the headlights on high beam.
2. Have your assistant increase the engine speed to approximately 2000 rpm.
3. Read the voltage across the battery terminals again.
1. If the voltage increase is 0.5 volts over the base voltage measured in Battery No−Load test
Step 3, the charging system is working properly. If your problem continues, there may be a
problem with the battery.
2. If the voltage does not increase as indicated, perform the Alternator Load and No−Load tests.
Alternator Load Test
Do NOT use a normal Digital Volt Ohmmeter (DVOM) for this test; your DVOM will be destroyed by the
large amounts of amperage from the car's battery. Use a tester designed for charging system analysis, such as
the Rotunda Alternator, Regulator, Battery and Starter Motor Tester 010−00725 (ARBST) or equivalent.
1. Switch the tester to the ammeter setting.
2. Attach the positive (+) and negative (−) leads of the tester to the battery terminals.
3. Connect the current probe to the B+terminal on the alternator.
4. Start the engine and have an assistant run the engine at 2000 rpm. Adjust the tester load bank to
determine the output of the alternator. Alternator output should be within ten percent of the
alternator's output rating; if so, continue with the Alternator No−Load test. If the output is not within
ten percent of the alternator's output rating, there is a problem in the charging system. Have the
system further tested by a Ford qualified automotive technician.
Alternator No−Load Test
1. Using the same tester as in the Alternator Load Test, switch the tester to the voltmeter function.
2. Connect the voltmeter positive (+) lead to the alternator B+terminal and the negative (−) lead to a
good engine ground.
3. Turn all of the electrical accessories off and shut the doors.
4. While an assistant operates the engine at 2000 rpm, check the alternator output voltage. The voltage
should be between 13.0−15.0 volts. If the alternator does not produce voltage within this range there
is a problem in the charging system. Have the system further tested by a Ford qualified automotive
technician.
REMOVAL & INSTALLATION
1. Disconnect the negative battery cable.
2. Remove the accessory drive belt.
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HOW TO USE THIS BOOK
WARNING
TESTING