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Home >> Mazda >> 2001 >> Protege ES, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.0L >> Diagnostic Tests >> DTC P0123: Throttle Position (TP) Sensor Circuit, High Input >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Ensure FREEZE FRAME DATA has been recorded. Check for related service bulletins. Repair as necessary and go to next step.
  2. Disconnect TP connector. Check connector and terminals. If no problem is found, go to next step. If problem is found, repair as necessary and go to step  7 .
  3. Check resistance between TP sensor terminals "A" (Pink/Black wire) and "B" (Orange wire). Resistance should be 3200-4800 ohms. Check resistance between TP sensor terminals "B" (Orange wire) and "C" (Brown/Yellow wire). Resistance should be 200-1200 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace TP sensor. Go to step  7 .
  4. Check continuity between TP sensor harness connector terminal "B" (Orange wire) and ground. See Figure . If continuity is present, go to next step. If continuity does not exist, repair open in Orange wire. See WIRING DIAGRAMS article. Go to step  6 .
  5. Disconnect PCM connector. Check connector and PCM terminals. If any problem is found, repair as necessary and go to step  7 . If no problem is found, go to step  7 .
  6. Check continuity between TP sensor harness connector terminals "A" (Pink/Black wire) and "C" (Brown/Yellow wire). See Figure . If continuity is not present, go to next step. If continuity is present, repair short between circuits and go to next step.
  7. Reconnect all connectors. Start engine. Clear DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. Race engine a few times. Check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC P0123 is present, replace PCM and go to next step. If DTC P0123 is not present, go to next step.
  8. Cycle ignition from off to on. Check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If any other DTC is present, go to appropriate test.
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