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Home >> Lexus >> 2002 >> IS 300 Base, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 37 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P2102: Throttle Actuator Control Motor Circuit Low Or DTC P2103: Throttle Actuator Control Motor Circuit High >> Diagnosis & Repair (Using OBD-II Scan Tool)
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Diagnosis & Repair (Using OBD-II Scan Tool)

WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.
  1. Connect the oscilloscope between terminals M+ or M- and E1 of the ECM connectors. Start the engine. Check the waveform between terminals M+ or M- and E1 of the ECM connectors when the engine is idling. The pulse width varies depending on the throttle opening. See Fig 1. If okay, check and replace ECM. If not okay, go to next step.
    Fig 1: Identifying Throttle Control Motor Oscilloscope Waveform
    G00165164Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Check throttle control motor. See THROTTLE CONTROLS in SYSTEMS & COMPONENT TESTING article. Replace throttle body as necessary. If okay, go to next step.
  3. Check for open and short in harness and connector between throttle control motor and ECM. Repair as necessary. If okay, replace ECM.
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