LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Plymouth >> 2000 >> Prowler >> Repair and Diagnosis >> Electrical >> Charging Systems >> Charging System - Generators & Regulators >> Diagnosis & Testing >> Charging System >> Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Charging System: Test

  1. Start engine.
  2. Place heater blower in high position.
  3. Turn on headlamps and place in high-beam position.
  4. Turn vehicle interior lamps on.
  5. Bring engine to 2400 rpm and hold.
  6. Test battery positive (+) circuit using the following procedure:
    • Touch negative lead of voltmeter directly to battery positive POST. See Figure .
    • Touch positive lead of voltmeter to B+ output terminal stud on generator (not terminal mounting nut). Voltage should be no higher than .6 volt. If voltage is higher than .6 volt, touch test lead to terminal mounting stud nut and then to wiring connector. If voltage is now below .6 volt, look for dirty, loose or poor connection at this point. Also check condition of generator output wire-to-battery bullet connector. A voltage drop test may be performed at each (ground) connection in this circuit to locate excessive resistance.
  7. Test battery negative (- ground) circuit using the following procedure:
    • Touch positive lead of voltmeter directly to battery negative POST.
    • Touch negative lead of voltmeter to generator case. Voltage should be no higher than .3 volt. If voltage is higher than .3 volt, touch test lead to generator case and then to engine block. If voltage is now below .3 volt, look for dirty, loose or poor connection at this point. A voltage drop test may be performed at each connection in this circuit to locate excessive resistance. This test can also be performed between generator case and engine. If test voltage is higher than .3 volt, check for corrosion at generator mounting points or loose generator mounting.


  1. Perform test Preparation procedure has been performed. Fully engage parking brake. Start engine. Bring engine speed to 2500 rpm. With engine speed held at 2500 rpm, slowly adjust rheostat control (load) on tester to obtain highest amperage reading. DO NOT allow voltage to drop below 12 volts. Record reading. This load test must be performed within 16 seconds to prevent damage to test equipment. On some test equipment, load will be applied automatically.
  2. The ammeter reading must meet Minimum Test Amps specifications. A label stating a part reference number is attached to generator case. On some engines this label may be located on bottom of case. Compare this reference number to Generator Ratings chart.
  3. Rotate load control to OFF position. Continue holding engine speed at 2500. If EVR circuitry is okay, amperage should drop below 15-20 amps. With all electrical accessories and vehicle lighting off, this could take several minutes of engine operation. If amperage did not drop. Remove volt/amp tester. If minimum amperage could not be met.
scientia non olet · About LEMON Manuals