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Home >> Suzuki >> 2001 >> Esteem GL, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - Esteem 1.8L >> Diagnostic Tests >> DTC P0123: High Throttle Position Sensor Circuit Input >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST  . If DTC P0123 is set, go to next step. If DTC P0123 is not set, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  2. Turn ignition off. Connect scan tool. Turn ignition on. Observe throttle valve opening percentage on scan tool while slowly opening throttle valve to fully open position. If display reads 100 percent trough entire range, go to next step. If display does not read 100 percent through entire range, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  3. Turn ignition off. Disconnect TP sensor connector. Check for poor terminal contact at TP sensor connector. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST  . If terminal contact is okay, turn ignition on. Measure voltage between ground and TP sensor harness connector terminal No. 2 (Gray wire) and No. 3 (Pink/Green wire), individually. If 4-6 volts are present at each terminal, go to step  5 . If 4-6 volts are not present at each terminal, go to next step.
  4. Check for short to power in Pink/Green wire between TP sensor and ECM 28-pin connector C20 terminal No. 18. Also check for open in Gray wire between TP sensor and ECM 28-pin connector C20 terminal No. 25. See WIRING DIAGRAMS article. Repair as necessary. If wires are okay, check for poor terminal contact at ECM 28-pin connector C20. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST  . If terminal contact is okay, replace ECM and go to DTC CONFIRMATION TEST  .
  5. Measure resistance between TP sensor terminal No. 1 (Orange wire) and No. 3 (Pink/Green wire). Resistance should be 4-6 k/ohms. Also measure resistance between TP sensor terminal No. 1 (Orange wire) and No. 2 (Gray wire). Resistance should be 0.1-6.5 k/ohms (measurement will vary according to throttle valve opening). If readings are not as specified, replace TP sensor and go to DTC CONFIRMATION TEST  . If readings are as specified, go to next step.
  6. Check for open in Orange wire between TP sensor and ECM 28-pin connector C20 terminal No. 27. See WIRING DIAGRAMS article. Repair as necessary. If wire is okay, check for poor terminal contact at ECM 28-pin connector C20. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST  . If terminal contact is okay, replace ECM and go to DTC CONFIRMATION TEST  .
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