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Home >> Toyota >> 2003 >> Matrix Base, FWD, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 30 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P1127: Electronic Throttle Control System (ETCS) Actuator Power Source Circuit Malfunction >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check ETCS fuse (10-amp) from junction block located at left side of engine compartment. If ETCS fuse is okay, go to next step. If ETCS fuse is blown, check for short circuit in wiring harness between ETCS fuse and ECM. See WIRING DIAGRAMS article. Repair wiring as necessary.
  2. Access ECM behind glove box. Backprobing, measure voltage between ECM terminal No. 4 (White/Black wire) at ECM E8 connector and terminal No. 6 (Blue/Red wire) at ECM E7 connector. See Figure. If voltage is 9-14 volts, go to next step. If voltage is not 9-14 volts, replace ECM.
  3. Check wiring between battery, ETCS fuse, ETCS fuse and ECM. See WIRING DIAGRAMS article. Repair wiring as necessary. If wiring is okay, replace ECM.
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