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Home >> Saturn >> 2000 >> LS2 Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0403: EGR Solenoid Control Circuit >> Diagnostic Procedures
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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. Using scan tool, command EGR on while monitoring EGR sensor. If voltage changes when EGR is commanded on, go to next step. If voltage does not change when EGR is commanded on, go to step  4.
  3. Disconnect EGR solenoid harness connector. Using a DVOM, check voltage on EGR solenoid harness connector terminal "A" (Black/White wire). If 2-4 volts are present, problem is intermittent. See DIAGNOSTIC AIDS . If 2-4 volts are not present, replace ECM.
  4. Check ENG CNTL 1 fuse located in underhood fuse/relay block. Replace as necessary. Disconnect EGR solenoid harness connector. Connect a test light between EGR solenoid harness connector terminals "A" (Black/White wire) and "E" (Orange wire). Using scan tool, command EGR on. If test light illuminates, check for terminal tightness at connectors. Repair as necessary. If terminals are okay, replace EGR solenoid. If test light does not illuminate, go to next step.
  5. Connect test light between ground and EGR solenoid harness connector terminal "E" (Orange wire). If test light does not illuminate, repair open in Orange wire to fuse block. If test light illuminates, check for open in circuit between EGR solenoid harness connector terminal "A" (Black/White wire) and fuse block. Repair as necessary. If circuit is okay, check for terminal tightness at connectors. Repair as necessary. If terminals are okay, replace ECM.
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