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Home >> Suzuki >> 2001 >> Vitara JS, 4D Utility, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0122: Throttle Position (TP) Sensor Circuit, Low Input >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST . If DTC P0122 is set, go to next step. If DTC P0122 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. Select TP sensor parameter on scan tool. Observe scan tool display while depressing accelerator pedal to full throttle position. If scan tool display remains at zero percent, go to next step. If scan tool display does not remain at zero percent, 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 Gray/Red wire terminal. See WIRING DIAGRAMS article. If reading is 4-6 volts, go to step  5. If reading is not 4-6 volts, go to next step.
  4. Check for an open or short to ground in Gray/Red wire between PCM 26-pin connector C51-3 terminal No. 13 and TP sensor. If wire is okay, disconnect PCM 26-pin connector C51-3. Check for poor terminal contact at PCM 26-pin connector C51-3. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, replace PCM and go to DTC CONFIRMATION TEST .
  5. Check TP sensor operation. See SENSORS & SWITCHES in SYSTEM & COMPONENT TESTING article. Replace as necessary. If TP sensor operation is okay, check for short or open in Red/Green wire between TP sensor and PCM 26-pin connector C51-3 terminal No. 9. If wire is okay, disconnect PCM 26-pin connector C51-3. Check for poor terminal contact at PCM 26-pin connector C51-3. If poor terminal contact is found, repair as necessary and go to DTC CONFIRMATION TEST . If terminal contact is okay, replace PCM and go to DTC CONFIRMATION TEST .
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