Generator Test

TOOLS REQUIRED
^ SA9154Z-A Starting and Charging System Tester

The following procedure is outlined step-by-step using the Starting and Charging System Tester SA9154Z-A.

CAUTION: SAFETY GLASSES SHOULD BE WORN AND RINGS, WATCHES, AND ALL OTHER HAND JEWELRY SHOULD BE REMOVED.

IMPORTANT: If a fusible link is blown, don't just replace it. The most probable cause of a blown link is an internal generator failure. Verify that there is no external arcing or shorting of fusible link with other wires and/or components. If no problems are found, replace generator.

1. Verify the fusible link between the starter and generator is good. Also verify connections are tightened to specification and clean. (Charging system light functional test will verify link is ok.)
2. Turn system tester On. Connect large red tester cable to battery positive (+). Connect large black tester cable to battery negative (-). Place gray inductive current pick-up around battery positive (+) cable. Make sure that arrow on the gray inductive current pick-up pointing toward starter motor solenoid.

NOTE: Verify inductive current pick-up is completely closed around cable.

3. Place gray inductive current pick-up around battery positive cable between battery positive terminal and starter motor solenoid connection. The positive cable is covered by plastic conduit. This conduit does not need to be removed before testing.

NOTE: A flat battery will adversely affect Charging System Test results. Perform Battery Test before performing Charging System Test.

4. Perform BATTERY LOAD TEST to verify a good battery. (Refer to "Battery Load Test".) Battery Load Test
5. Start vehicle and turn all accessories Off.
6. Follow the system tester procedures.




7. Press CHARGING SYSTEM TEST. The display should show the correct number of cylinders. To change the number of cylinders, simply press that number on the keypad.

Results
^ The tester will display the voltage and current output of the generator.

Voltage
^ With a good battery in the vehicle, the voltage output should be between 13 and 15.5 V.

Diode Pattern
^ Always ignore this test.

If the generator does not pass the above voltage and current tests.
1. Output current is below 20 A, verify charge warning telltale operation on I/P cluster. (Refer to "Diagnostic Aids".)
2. Output current is above 20 A but below specified minimum current, verify gray amp. Probe is properly installed and belt is in good condition. If both pass, replace generator.