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Generator Load Test

CAUTION: To prevent damage to the generator, do not make jumper wire connections except as directed. Do not allow any metal object to come in contact with the housing and the internal diode cooling fins with key on or off. A short circuit will result and burn out the diodes.
NOTE: Prior to performing generator testing, turn OFF all electrical components. Place transmission in NEUTRAL, apply parking brake.
  1. Turn ignition switch to OFF position. Switch battery tester to ammeter function. Connect positive and negative leads to corresponding battery terminals. Connect current probe to generator battery output terminal wire (Black/Orange wire).
  2. With the engine running, turn the A/C on, the blower motor on high speed and the headlamps on high beam. Increase the engine speed to approximately 2000 RPM. The voltage should increase a minimum of 0.5 volt above the base voltage:
    • If the voltage does not increase as specified, go to next step.
    • If the voltage increases as specified, the charging system is operating normally.
  3. With the engine running at 2000 RPM, adjust the tester load bank to determine the output of the generator. Generator output should be within specification. See GENERATOR SPECIFICATIONS  table under GENERATOR SPECIFICATIONS. If generator output is not within specification, replace generator. See GENERATOR  under REMOVAL & INSTALLATION.