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Home >> Toyota >> 2004 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 39 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P1128: Throttle Control Motor Lock Circuit >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2002 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition off. Disconnect throttle control motor Gray 4-pin harness connector. Measure resistance between terminals No. 1 (White wire terminal) and No. 2 (Red wire terminal) at throttle control motor (component side). Resistance should be .3-100.0 ohms at 68°F (20°C). If resistance is as specified, go to next step. If resistance is not as specified, replace throttle control motor.
  2. Remove air inlet hose from throttle body. Visually inspect throttle body for carbon build-up or foreign material holding throttle valve open. If problem exists, repair as necessary. If problem does not exist, replace throttle body.