Bench Testing: Rotor

1998 Lexus GS 300SECTION Rotor
  1. Check rotor for open field windings by measuring resistance across slip rings. Rotor resistance should be within rotor specifications. See ROTOR RESISTANCE SPECIFICATIONSΒ  table. Check rotor for short circuit to ground by connecting ohmmeter between one slip ring and rotor shaft. Continuity should not exist.
  2. Check slip rings for wear or damage. Turn rotor/slip rings on lathe if necessary. Ensure slip ring diameter is not less than .504" (12.8 mm). Check bearing and replace if necessary.
ROTOR RESISTANCE SPECIFICATIONS (1)

Application Ohms
ES300, LS400 & SC300 2.1-2.5
GS300 & GS400 2.2-2.4
SC400 2.7-3.1
(1) Measured at 77Β°F (25Β°C).
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
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