Mitsubishi Raider 2006

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Diagnosis & Testing



Generator Output Current Test

This test is designed to judge whether or not the generator gives an output current that is equivalent to the nominal output.

Test Preparation
  1. Check the battery that installed in the vehicle, making sure it is in good sound state. Test the battery as required to assure this. The battery used to check output current should be one that has been rather discharged. With a fully discharged battery, the test may not be conducted correctly due to an insufficient load.
  2.  
  3. Check the generator drive belt for proper tension, as outlined in Section 1.
  4.  
  5. Make sure the ignition switch is turned OFF . Disconnect the battery ground cable.
  6.  
  7. Disconnect the generator output lead from the generator B terminal.
  8.  
  9. Connect the positive lead of an ammeter to the 1 terminal and the negative lead to the disconnected output wire.
    NOTE
    Tighten each connection by bolt and nuts securely as a heavy current will flow through the wire. Do not rely on clips.

  10.  
  11. Connect a voltmeter between the B terminal and ground. Connect the positive lead wire to the generator B terminal and the negative lead wire to a sound ground.
  12.  
  13. Connect the battery ground cable.
  14.  
  15. Leave the hood open.
  16.  

Test Procedure
  1. Check to see that the voltmeter reads the same value as the battery voltage. If the voltmeter reads 0 volts, an open circuit in the wire between the generator B terminal and the battery negative terminal, a blown fuse link, or poor grounding is suspected.
  2.  
  3. Turn the headlight switch on and start the engine.
  4.  
  5. Set the headlights at high beam and the heater blower switch at high, quickly increase the engine speed to 2,500 rpm and read the maximum output current value indicated by the ammeter.
    NOTE
    After engine start up, the charging current drops quickly, therefore, above operation must be done quickly to read the maximum current value correctly.

  6.  
  7. The ammeter reading must be higher than the limit value. If it is lower than the limit value but the generator output wire is normal, remove the generator from the vehicle and check it further. The limit values are as follows:
    NOTE
    The nominal output current value is shown on the nameplate affixed to the generator body. The output current value changes with the electrical load and the temperature of the generator itself. Therefore, the nominal output current may not be obtained if the vehicle electrical load at the time of the test is small. In such case, keep the headlights on to cause discharge of the battery to increase the electrical load. The nominal output current may not be obtained if the temperature of the generator itself or ambient temperature is too high.



    65A generator-45.5A minimum
     
    75A generator-52.5A minimum
     

  8.  
  9. Upon completion of the test, lower the engine speed to idle and turn the ignition switch OFF .
  10.  
  11. Disconnect the battery ground cable.
  12.  
  13. Disconnect and remove the engine tachometer, voltmeter and ammeter connected for the purpose of this test.
  14.  
  15. Connect the generator output wire.
  16.  
  17. Connect the battery ground cable.
  18.  

Generator Output Wire Voltage Drop

This test will determine whether or not the wiring (including the fusible link) between the generator B terminal and the battery positive terminal is sound by voltage drop method. A clamp type ammeter that can measure current without disconnecting the harness is preferred for this test.

Test Preparation
  1. Turn the ignition OFF .
  2.  
  3. Disconnect the battery ground cable.
  4.  
  5. Disconnect the generator output lead from the generator B terminal.
  6.  
  7. Connect the positive lead of an ammeter to the B terminal and the negative lead to the disconnected output wire.
  8.  
  9. Connect a digital voltmeter between the generator B terminal and the battery positive terminal. Connect the positive lead wire of the voltmeter to the B terminal and the negative lead wire to the battery positive terminal.
  10.  
  11. Connect the battery ground cable.
  12.  
  13. Leave the hood to the engine compartment open.
  14.  

Test Procedure
  1. Start the engine.
  2.  
  3. Turn the headlamps and small lamps ON and adjust the engine speed so that the ammeter reads 20A. Note the voltmeter indication under this condition.
  4.  
  5. It is OK if the voltmeter reads the standard value of 0.2V max.
  6.  
  7. If the voltmeter indicates a value larger than the standard value, poor wiring is suspected, in which case check the wiring from the generator B terminal to the fuse link to battery positive terminal. Check for loose connection, color change due to overheating hardness, etc. and correct before testing again.
  8.  
  9. Upon completion of the test, set the engine speed at idle.
  10.  
  11. Turn the lights and the ignition switch OFF .
  12.  
  13. Disconnect the battery ground cable.
  14.  
  15. Disconnect the ammeter and the voltmeter that have been connected for the purpose of the test.
  16.  
  17. Connect the generator output wire to the generator B terminal.
  18.  
  19. Connect the battery ground cable.
  20.  

 
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