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Home >> Suzuki >> 2002 >> XL-7 Plus >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (Engine Controls - Self-Diagnostics - 2.2L) >> Diagnostic Tests >> DTC P0406: Exhaust Gas RECIRCULATION System - Circuit High Input >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Isuzu Rodeo Sport and 2002 Isuzu Rodeo. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform ON-BOARD DIAGNOSTIC II SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD-II system check, go to next step.
  2. Turn ignition on. Using scan tool, read and record FAILURE RECORDS data for DTC P0406. Clear DTCs. Operate vehicle within conditions noted in FAILURE RECORDS data. Using scan tool, monitor specified DTC parameters. If scan tool displays DTC P0406 RAN AND PASSED, check for intermittent problem. See DIAGNOSTIC AIDS  . If scan tool does not display DTC P0406 RAN AND PASSED, go to next step.
  3. Turn ignition off. Disconnect EGR valve 5-pin harness connector. EGR valve is located at top rear of engine. Turn ignition on. Using DVOM, measure voltage between ground and EGR valve harness connector terminal No. 5 (Black/Yellow wire). If battery voltage exists, go to step  6 . If battery voltage does not exists, go to next step.
  4. Check for open or short to ground in Black/Yellow wire (ignition feed) between EGR valve and CB-12 ENGINE IG (15-amp) fuse. See WIRING DIAGRAMS article. If problem is found, repair as necessary. After repair is completed, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
  5. Using DVOM, measure resistance between EGR solenoid terminals No. 1 and 5 (component side). Resistance should be less than 5 ohms. If resistance is as specified, go to next step. If resistance more than specified, go to step  14 .
  6. Check for open, short to ground or short to voltage in Yellow wire (EGR solenoid low) between PCM and EGR valve. See WIRING DIAGRAMS article. If problem is found, repair as necessary. After repair is completed, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM. If no problem was found, go to step  15 .
  7. Turn ignition off. Disconnect EGR valve 5-pin harness connector. EGR valve is located at top rear of engine. Turn ignition on. On scan tool, observe EGR valve parameters. If parameters are zero volts and zero percent, go to step  9 . If parameters are not as specified, leave harness connector disconnected and go to next step.
  8. Check for open, short to ground or short to voltage in Yellow/Red wire (EGR valve position) between PCM and EGR valve. See WIRING DIAGRAMS article. If problem is found, repair as necessary. After repair is completed, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM. If no problem was found, leave harness connector disconnected and go to next step.
  9. Using DVOM, measure voltage between ground and EGR valve harness connector terminal No. 4 (Blue/Orange wire). Voltage reading should be about 5 volts. If voltage is as specified, go to step  11 . If voltage is not as specified, leave harness connector disconnected and go to next step.
  10. Check for open, short to ground or short to voltage in Blue/Orange wire (5-volt reference) between PCM and EGR valve. See WIRING DIAGRAMS article. If problem is found, repair as necessary. After repair is completed, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM. If no problem was found, leave harness connector disconnected and go to next step.
  11. Turn ignition on. Measure voltage between EGR valve harness connector terminals No. 2 (Blue/Yellow wire) and No. 4 (Blue/Orange wire). Voltage reading should be about 5 volts. If voltage is as specified, go to step  13 . If voltage is not as specified, leave harness connector disconnected and go to next step.
  12. Check for open, short to ground or short to voltage in Blue/Yellow wire (EGR valve ground) between PCM and EGR valve. See WIRING DIAGRAMS article. If problem is found, repair as necessary. After repair is completed, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM. If no problem is found, go to step  15 .
  13. Turn ignition off. Using a fused jumper wire, jumper EGR valve harness connector terminals No. 3 (Yellow/Red wire) and No. 4 (Blue/Orange wire). Turn ignition on. On scan tool, observe EGR valve parameters. If parameters are 5 volts and 100 percent, go to next step. If parameters are not as specified, go to step  15 .
  14. Replace EGR valve. See REMOVAL, OVERHAUL & INSTALLATION article. After repair is completed, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
  15. Replace and reprogram PCM. See POWERTRAIN CONTROL MODULE REPLACEMENT  under POWERTRAIN CONTROL MODULE. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
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