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Home >> Suzuki >> 2001 >> Swift GA, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0450: EVAP System Pressure Sensor Malfunction >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. Perform DTC CONFIRMATION TEST . If DTC P0450 is set, go to next step. If DTC P0450 is not set, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article.
  2. Check for DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES  under SELF-DIAGNOSTIC SYSTEM. If DTC P0107, P0122 and P0450 are set, check for open in Light Green wire between PCM 16-pin connector C22 terminal No. 1 and FTP sensor connector terminal No. 3. Also check for open in Light Green/Black wire between PCM 22-pin connector C23 terminal No. 22 and FTP sensor connector terminal No. 2. See Figure. See WIRING DIAGRAMS article. Repair as necessary and go to DTC CONFIRMATION TEST . If DTC P0107, P0122 and P0450 are not present and/or wires are okay, go to next step.
  3. If not using scan tool, go to next step. If using scan tool, turn ignition off and connect scan tool. Open fuel filler cap. Turn ignition on. Scan tool should display FUEL TANK PRESSURE of 0 in. Hg. If reading is as specified, go to step  6. If reading is not as specified, go to step  5.
  4. Open fuel filler cap. Turn ignition on. Measure voltage (backprobe) between ground and PCM 22-pin connector C23 terminal No. 21 (Light Green/Yellow wire). See Figure. If reading is not 2-2.5 volts, go to next step. If reading is 2-2.5 volts, go to step  6.
  5. Check FTP sensor operation. See FUEL TANK PRESSURE SENSOR under FUEL EVAPORATION in SYSTEM & COMPONENT TESTING article. Replace as necessary and go to DTC CONFIRMATION TEST . If FTP sensor is okay, check for short or open in circuits between FTP sensor and PCM. See WIRING DIAGRAMS article. If circuits are okay, replace PCM and go to DTC CONFIRMATION TEST .
  6. Check FTP sensor operation. See FUEL TANK PRESSURE SENSOR under FUEL EVAPORATION in SYSTEM & COMPONENT TESTING article. Replace as necessary and go to DTC CONFIRMATION TEST . If FTP sensor is okay, go to next step.
  7. Check Fuel Tank Pressure Control Valve (FTPCV) operation. See SYSTEM & COMPONENT TESTING article. Replace as necessary and go to DTC CONFIRMATION TEST . If FTPCV is okay, problem is intermittent. System is okay at this time. See TROUBLE SHOOTING - NO CODES article. If intermittent problem is not found, replace PCM and go to DTC CONFIRMATION TEST .
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