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Generator Output

  1. Connect charging system test equipment following manufacturer's instructions. Check charging system output voltage at 2000 RPM. If output voltage is high, replace voltage regulator and retest. If output voltage is low, go to next step. If output voltage is correct, go to step 3). See GENERATOR OUTPUT SPECIFICATIONS  table.
  2. If output voltage is low, by-pass regulator (full field generator) by grounding terminal "F" at back of generator. See Fig 1, Fig 2 or Fig 3 . Recheck charging system output voltage. If voltage now exceeds output voltage specified in GENERATOR OUTPUT SPECIFICATIONS  table, replace regulator and recheck. If output voltage is still incorrect, repair or replace generator.
  3. With engine at 2000 RPM, place the heater blower switch on highest setting and turn on headlights (high beam). Ammeter reading should be 30 amps or more. If amperage output is incorrect, repair or replace generator.
GENERATOR OUTPUT SPECIFICATIONS (1)

Application Amps Volts
ES300 & GS300 10 Or Less 13.2-14.8
GS400 10 Or Less 13.2-14.8
LS400 & SC400 10 Or Less 13.7-14.8
SC300 10 Or Less 13.2-14.8
(1) Measured at 77°F (25°C) and 2000 RPM.
Fig 1: Full Fielding Generator (ES300)
G93C01642Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Full Fielding Generator (LS400 & SC400)
G93E01643Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Full Fielding Generator (SC300 Shown; GS300 & GS400 Are Similar)
G93G01644Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002