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Home >> Saturn >> 2000 >> LS1 Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0340: Camshaft Position (CMP) Sensor Circuit >> Diagnostic Procedures

Diagnostic Procedures

  1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD system check, go to next step.
  2. Start engine. If an engine misfire is present, diagnose misfire first. See DTC P0301-P0304: CYLINDERS NO. 1-4 MISFIRE DETECTED . If an misfire is not present, go to next step.
  3. Operate engine at idle for about one minute. Using scan tool, observe CAL. COMPRESSION OUTPUT. If the last 4 digits are all zeros or ones, go to next step. If the last 4 digits are not all zeros or ones, problem is intermittent. See DIAGNOSTIC AIDS .
  4. If all the last 4 digits are ones, go to next step. If all the last 4 digits are zeros, go to step  7.
  5. Turn ignition off. Disconnect EI module harness connector. Turn ignition on, with engine off. Using a DVOM, check voltage on EI module harness connector terminal "F" (Brown/White wire). If voltage reading is greater than one volt, go to next step. If voltage reading is not greater than one volt, check circuit for short to voltage. Repair as necessary. If circuit is okay, replace PCM.
  6. Turn ignition off. Reconnect EI module harness connector. Connect Diagnostic Service Probe (DSP) to EI module harness connector terminal "F" (Brown/White wire). Start engine. Connect jumper from DSP to ground. Using scan tool, observe CAL. COMPRESSION OUTPUT. If the last 4 digits are now all zeros, replace EI module. If the last 4 digits are not all zeros, replace PCM.
  7. Turn ignition off. Disconnect EI module harness connector. Using a DVOM, check resistance between ground and EI module harness connector terminal "F" (Brown/White wire). If resistance is less than 40,000 ohms, check Brown/White wire for short to ground. Repair as necessary. If circuit is okay, replace PCM. If resistance is 40,000-60,000 ohms, go to next step. If resistance is greater than 60,000 ohms, check for open in Brown/White wire circuit or terminal tightness. Repair as necessary. If circuit or terminals are okay, replace PCM.
  8. Turn ignition off. Reconnect EI module harness connector. Connect Diagnostic Service Probe (DSP) to EI module harness connector terminal "F" (Brown/White wire). Start engine. Connect a fused jumper wire from DSP to battery positive. Using scan tool, observe CAL. COMPRESSION OUTPUT. If the last 4 digits are now all ones, go to next step. If the last 4 digits are not all ones, check if fuse in jumper wire blew. If fuse is blown, replace EI module. If fuse is not blown, replace PCM.
  9. Check interconnect between EI module and ignition coil assembly for open circuit. Repair as necessary. If circuits are okay, replace EI module.
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