14.2STARTER SYSTEM TEST PROCEDURE

a. WIth charger UNPLUGGED, connect the tester clamps to the battery as it is situated in the vehicle: red to the positive(+) terminal, black to the negative (–) terminal. Rock each clamp back and forth to make a good connection.

NOTE: The battery must be good and fully charged for this test.

b.Only the live voltage will appear on the LED, unless the charger is plugged in, in which case the charge current is displayed and the FAIL LED is lit. The Starter test will be bypassed if attempting to select it, until current is removed. UNPLUG the charger. The PASS/FAIL LEDs will alternate blinking until a crank event is detected.

c.Start the vehicle.

d.Observe the final cranking voltage that appears on the LED:

If the Volts reading is greater than 9.6 volts, the Starting System is OK. The PASS LED will light.

If the Volts reading is less than 9.6 volts, there is a Starting System problem. The FAIL LED will light. Check connections, wiring, and starter.

NOTE: If charge voltage exceeds 19.9v, the FAIL LED lights to highlight a potentially dangerous situation.

14.3CHARGING SYSTEM (ALTERNATOR) TEST PROCEDURE

The Alternator test is normally selected AFTER the crank (Starter) test. If continuing from a Starter test, with the vehicle still running, press the Function button to move from Starter to Alternator test.

a.Connect the tester clamps to the battery: red to positive (+) terminal, black to negative

(–) terminal, if they are not already connected. Rock each clamp back and forth to make a good connection. NOTE: The battery must be good and fully charged for this test.

b.Only voltage will appear on the LED, unless the charger is plugged in, in which case the charge current is displayed and the FAIL LED is lit. The Alternator test will be invalidated until current is removed. UNPLUG the charger.

c.Rev the engine at 2000 rpm for 15 seconds. The PASS/FAIL LEDs will indicate the result immediately. But as this is a semi-live result that will retain the highest measured value, it is recommended to wait until this peak voltage stabilizes. If the value drifts into the pass region, the PASS LED will light. If the value further drifts up and out of the pass region, then the FAIL LED will stay lit.

d.Observe the volts reading that appears on the LED:

If the Volts reading is between 13.3 and 15.5 volts, the Charging System is OK. The PASS LED will light.

If the Volts reading is greater than 15.5 volts, there is a Charging System Problem. The FAIL LED will light. Check regulator.

If the Volts reading is less than 13.3 volts there is a Charging System Problem. The FAIL LED will light. Check connections, wiring, and starter.

NOTE: If charge voltage exceeds 19.9v, the FAIL LED lights to highlight a potentially dangerous situation.

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Schumacher 85-8100 instruction manual Starter System Test Procedure, Charging System Alternator Test Procedure