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Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 5:  This step tests for a high resistance in the 5-volt reference or low reference circuit of the EGR valve.
  2. 7:  This step tests for a high resistance in the signal circuit of the EGR valve.
Step Action Values Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Control Module Connector End Views  or  Engine Controls Connector End Views 
1 Did you perform the Diagnostic System Check - Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls
2 Is DTC P0404, P0405, P0406, or P1403 also set? - Go to Diagnostic Trouble Code (DTC) List Go to Step 3 
3
  1. Turn ON the ignition, with the engine OFF.
  2. Observe the EGR Position Sensor parameter with a scan tool.
Is the voltage within the specified range?		 0.60-0.80 Volts Go to Step 4  Go to Step 5 
4
  1. Observe the Freeze Frame/Failure Records data for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Operate the vehicle within the Conditions for Running the DTC.
Did the DTC fail this ignition?		 - Go to Step 5  Go to Intermittent Conditions
5 
  1. Turn OFF the ignition.
  2. Disconnect the exhaust gas recirculation (EGR) valve.
  3. Turn ON the ignition, with the engine OFF.
    4. IMPORTANT: Use a test lamp that measures between 25-30 ohms.
  4. Connect a test lamp between the 5-volt reference circuit and the low reference circuit of the EGR valve position sensor.
Does the test lamp illuminate?		 - Go to Step 7  Go to Step 6 
6 Connect a test lamp between the 5-volt reference circuit of the EGR valve position sensor and a good ground.
Does the test lamp illuminate?		 - Go to Step 9  Go to Step 8 
7 
  1. Connect a 3-ampere fused jumper wire between the signal circuit and the low reference circuit of the EGR valve position sensor.
  2. Observe the EGR Position Sensor parameter on the scan tool.
Is the parameter less than the specified value?		 0.05 Volts Go to Step 11  Go to Step 10 
8 Test the 5-volt reference circuit of the EGR valve position sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 15  Go to Step 12 
9 Test the low reference circuit of the EGR valve position sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 15  Go to Step 12 
10 Test the signal circuit of the EGR valve position sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 15  Go to Step 12 
11 Test the EGR valve for the following:
Did you find and correct the condition?		 - Go to Step 15  Go to Step 13 
12 Test for an intermittent and for a poor connection at the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections and Repairing Connector Terminals in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 15  Go to Step 14 
13 Replace the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement (Non European Emissions) or Exhaust Gas Recirculation Valve Replacement (European and North American Emissions) .
Did you complete the replacement?		 - Go to Step 15  -
14 Replace the ECM. Refer to Engine Control Module Replacement .
Did you complete the replacement?		 - Go to Step 15  -
15
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC.
Did the DTC fail this ignition?		 - Go to Step 2  Go to Step 16 
16 Are there any DTCs that have not been diagnosed? - Go to Diagnostic Trouble Code (DTC) List System OK
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