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DTC Troubleshooting

DTC DIAGNOSTIC TROUBLESHOOTING CHART

Step Action YES NO
1  Was "Engine and Emission Control System Check" performed?  Go to Step 2. Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK .
2  Is there DTC P0403 (EGR circuit malfunction)?  Go to DTC P0403: Exhaust Gas Recirculation Control Circuit . Go to Step 3.
3  Do you have SUZUKI scan tool?  Go to Step 4. Go to Step 6.
4  EGR valve operation check 
  1. With ignition switch turned OFF, connect SUZUKI scan tool to DLC.
  2. Check EGR system referring to EGR VALVE ASSEMBLY INSPECTION .

Is it in good condition? 		 Go to Step 5. Go to Step 7.
5  EGR passage check 
  1. Check EGR passage for clog or leakage.

Is it in good condition? 		 Go to Step 6. Repair replace.
6  MAP sensor check 
  1. Check MAP sensor for performance referring to MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR INSPECTION .

Is check result satisfactory? 		 Intermittent trouble or faulty ECM. Check for intermittent referring to INTERMITTENT AND POOR CONNECTION INSPECTION . Repair or replace.
7  EGR valve power supply circuit check 
  1. With ignition switch turned OFF, disconnect EGR valve coupler.
  2. With ignition switch turned ON, measure voltage between each "BLU/BLK" wire terminal and ground at EGR valve coupler.

Is each voltage 10 - 14 V? 		 Go to Step 8. Faulty "BLU/BLK" wire.
8  EGR valve stepper motor coil circuit check 
  1. With ignition switch turned OFF, connect EGR valve coupler.
  2. Remove ECM cover and disconnect ECM couplers.
  3. Measure resistance between "C51-3-4" terminal and each terminal of "C51-2-12", "C51-2-13", "C51-2-14", "C51-2-15" at ECM couplers disconnected.

Is each resistance 20 - 24 Ω at 20 ° C (68 °F)? 		 Go to Step 9. Faulty EGR valve.
9  MAP sensor check 
  1. Check MAP sensor for performance referring to MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR INSPECTION .

Is check result satisfactory? 		 EGR passage clogged or EGR valve malfunction. If all above are OK, intermittent trouble or faulty ECM. Check for intermittent referring to INTERMITTENT AND POOR CONNECTION INSPECTION . Repair or replace.
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