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Home >> Suzuki >> 2003 >> Aerio S, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0340: Camshaft Position Sensor - Circuit Malfunction >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

NOTE: For better performance and results of this diagnostic procedure, usage of appropriate wiring diagram is recommended. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
NOTE: Perform all voltage and resistance tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use an ohmmeter to isolate wiring harness shorts or opens.
  1. If engine system check has been performed, go to next step. If engine system check has not been performed, perform TEST D: ENGINE SYSTEM CHECK  under SYSTEM TESTS, then go to next step.
  2. Crank engine and check engine cranking speed. If engine cranking speed is okay, go to next step. If engine cranking speed is to slow or will not crank, see GENERATORS & REGULATORS in appropriate STARTING & CHARGING article.
  3. Check start engine signal referring to step  2 under DTC P0616: STARTER SIGNAL CIRCUIT - LOW. If starting signal circuit is okay, go to next step. If starting signal circuit is faulty, repair as necessary and repeat DTC CONFIRMATION TEST .
  4. Turn ignition switch to LOCK position. Disconnect CMP sensor 4-pin harness connector C22. See Figure. Turn ignition switch to ON position. Measure voltage between CMP sensor harness connector C22 terminals No. 1 (Black/Orange wire) and No. 2 (Black/Red wire). See Fig 1. If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go to step  8.
  5. Ensure ignition switch is on ON position. Measure voltage between ground and CMP sensor harness connector C22 terminal No. 2 (Black/Red wire). See Fig 1. If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair open circuit in Black/Red wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .
  6. Turn ignition switch to LOCK position. Measure resistance between CMP sensor harness connector C22 terminal No. 1 (Black/Orange wire). See Fig 1. If resistance is 5 ohms or more, go to next step. If resistance is 5 ohms or less, go to step  8.
  7. Ensure ignition switch is on LOCK position. Locate ECM. See Figure. Remove ECM. See ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL & INSTALLATION article. Reconnect ECM harness connectors and backprobe and measure resistance between ECM harness connector C45 terminal No. 26 (Black/Orange wire). See Figure. If resistance is less than 5 ohms, repair open or short circuit in Black/Orange wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .If resistance is 5 ohms or more, check ECM ground circuits (Black/Orange wire) and (Black wire) for open or short between ECM and ground. If ground circuits are faulty, repair as necessary and repeat DTC CONFIRMATION TEST . If ground circuits are okay, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .
  8. Turn ignition switch to ON position. Measure voltage between CMP sensor harness connector C22 terminal No. 4 (Yellow/Red wire). See Fig 1. If voltage is not 4-5 volts, go to next step. If voltage is 4-5 volts, go to step  11.
  9. Disconnect ECM harness connector C46. Measure resistance between ground and CMP harness connector C22 terminal No. 4 (Yellow/Red wire). See Fig 1. If resistance is infinity, go to next step. If any resistance is found, repair short to ground in Yellow/Red wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .
  10. Disconnect ECM harness connector C46. Measure voltage between ground and CMP harness connector C22 terminal No. 4 (Yellow/Red wire). See Fig 1. If voltage is zero volt, repair open circuit in Yellow/Red wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST . If any voltage is found, repair short to other circuits between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .
  11. Turn ignition switch to LOCK position. Disconnect ECM harness connector C46. See Figure. Measure resistance between ECM harness connector C46 terminal No. 10 (Yellow/Red wire) and CMP sensor harness connector C22 terminal No. 4 (Yellow/Red wire). See Figure and Fig 1 . If resistance is less than 3 ohms, go to next step. If resistance is 3 ohms or more repair short circuit in Yellow/Red wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .
  12. Reconnect ECM harness connectors. Turn ignition switch to ON position. Measure voltage between ground and CMP sensor harness connector C22 terminal No. 3 (Blue wire). See Fig 1. If voltage is not 4-5 volts, go to next step. If voltage is 4-5 volts, go to step  15.
  13. Turn ignition switch to LOCK position. Disconnect ECM harness connector C46. Measure resistance between ground and CMP sensor harness connector C22 terminal No. 3 (Blue wire). See Fig 1. If resistance is infinity, go to next step. If any resistance is found, repair short to ground in Blue wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .
  14. Turn ignition switch to ON position. Measure voltage between ground and CMP sensor harness connector C22 terminal No. 3 (Blue wire). See Fig 1. If voltage is zero volt, open circuit in Blue wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST . If any voltage is found, repair short to voltage in Blue wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .
  15. Turn ignition switch to LOCK position. Measure resistance between ECM harness connector C46 terminal No. 22 (Blue wire)and CMP sensor harness connector C22 terminal No. 3 (Blue wire). See Figure and Fig 1 . If resistance is less than 3 ohms, go to next step. If resistance is 3 ohms or more repair short circuit in Blue wire between CMP sensor and ECM. After repair, repeat DTC CONFIRMATION TEST .
  16. Using an oscilloscope, check CMP sensor signal waveform. See REFERENCE . If CMP sensor signal waveform is okay, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST . If CMP sensor signal waveform is faulty, replace CMP sensor. See CAMSHAFT POSITION SENSOR under ENGINE SENSORS & SWITCHES in REMOVAL & INSTALLATION article. After repair, repeat DTC CONFIRMATION TEST .
Fig 1: Identifying Camshaft Position Sensor Harness Connector C22 Terminals
G00232465Courtesy of SUZUKI OF AMERICA CORP.
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