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Generator Output

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2000 Lexus SC 400, 2000 Lexus SC 300, 2000 Lexus RX 300, 2000 Lexus LS 400, and 2000 Lexus GS 400. However, it is still accessible from the selected car via links, so may be relevant.
  1. Connect charging system test equipment following manufacturer's instructions. Check charging system output voltage at 2000 RPM. See GENERATOR OUTPUT SPECIFICATIONS  table. 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.
  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. See GENERATOR OUTPUT SPECIFICATIONS  table. If output voltage is high, replace voltage regulator and recheck. If output voltage remains low, repair or replace generator.
  3. With engine at 2000 RPM, place heater blower switch on highest setting and turn on headlights (high beam). Ammeter reading should be 30 amps or more. If amperage output is less than 30 amps, repair or replace generator.
GENERATOR OUTPUT SPECIFICATIONS

Application Amps Volts
ES300, GS300, GS400 & SC300 10 Or Less 13.2-14.8
LS400 & SC400 10 Or Less (1) 13.7-14.8
RX300 10 Or Less 13.5-15.1
(1) Measured at 77°F (25°C) and 2000 RPM.
Fig 1: Full Fielding Generator (ES300 & RX300)
G99G08056Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Full Fielding Generator (LS400 & SC400)
G99I08057Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Full Fielding Generator (SC300 Shown; GS300 & GS400 Are Similar)
G99A08058Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002