2. Replace the alternator if it fails the test. follow the paragraph «Generator» in the Vehicle Maintenance section of this section. If it passes the test, perform the power output test on the vehicle as follows.
Important: Always check the generator output power before assuming a generator failure from a short to terminal ground "L".
3. Attach a digital multimeter, ammeter, and carbon film resistor to the vehicle.
Important: Make sure the battery is fully charged and the carbon film resistor is disconnected.
4. With the ignition switch off, check and record the battery voltage.
5. Remove the wiring harness connector from the generator.
6. Turn the ignition to RUN with the engine off. Use a digital multimeter to check the voltage at the terminal "L" cable harness connector.
7. The reading should be approximately equal to the specified 12V battery voltage. If the voltage is too low, check the terminal circuit "L" short to ground and open circuit, which can cause a voltage drop. Repair wire breaks, terminal connections, etc. if necessary. follow the paragraph «Charging system» in this section.
8. Connect the generator harness connector.
9. Start the engine at medium idle and measure the voltage between the battery terminals. The reading should be greater than 13V but less than 16V. If the reading is greater than or less than 16V, the alternator must be replaced. follow the paragraph «Generator» Car maintenance of this section.
10. Run the engine at medium idle and measure the alternator output current.
11. Turn on the carbon film resistor and adjust it to get the maximum current when the battery voltage is above 13V.
12. If the reading is within the 15 amps marked on the alternator, the alternator is OK. If not, replace the alternator. follow the paragraph «Generator» Car maintenance of this section.
13. With the alternator running at full output, measure the voltage between the alternator case and the negative battery terminal. The voltage drop should be 0.5 V or less. If the voltage drop is greater than 0.5V, check the connection between the alternator case and the negative battery cable.
14. Check, clean, tighten and recheck all ground connections.
