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Test Description

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

  1. 6:  This step tests for an open in the ignition 1 voltage circuit of the EGR valve.
  2. 7:  This step tests for a short to ground in the control circuit of the EGR valve.
  3. 8:  This step tests for an open in the control circuit of the EGR valve.
  4. 10:  This step tests for high resistance in the control circuit of the EGR valve.
  5. 11:  This step tests for a high resistance in the 5-volt reference or low reference circuit of the EGR valve.
  6. 13:  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 
Connect End View Reference:  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 P0405 or P0406 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 11 
4
  1. Command the EGR valve from 0 percent to 100 percent with a scan tool.
  2. Observe the EGR Position Sensor parameter with a scan tool.
Is the voltage more than the specified value?		 3.70 Volts Go to Step 5  Go to Step 6 
5
  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 6  Go to Intermittent Conditions
6 
  1. Turn OFF the ignition.
  2. Disconnect the exhaust gas recirculation (EGR) valve.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the ignition 1 voltage circuit of the EGR valve and a good ground.
Does the test lamp illuminate?		 - Go to Step 7  Go to Step 20 
7  Connect a test lamp from the ignition 1 voltage circuit to the control circuit of the EGR valve.
Does the test lamp illuminate?		 - Go to Step 14  Go to Step 8 
8 
  1. Connect a test lamp from the ignition 1 voltage circuit to the control circuit of the EGR valve.
  2. Command the EGR valve to 100 percent.
Does the test lamp illuminate?		 - Go to Step 9  Go to Step 14 
9
  1. Turn OFF the ignition.
  2. Disconnect the fuse that supplies ignition 1 voltage to the EGR valve.
  3. Measure the resistance of the ignition 1 voltage circuit of the EGR valve from the fuse terminal to the harness connector terminal of the EGR valve.
Is the resistance less than the specified value?		 3 Ω Go to Step 10  Go to Step 20 
10 
  1. Turn ON the ignition, with the engine OFF.
  2. Probe the control circuit of the EGR valve with a test lamp connected to battery positive voltage.
  3. Command the EGR valve to 100 percent.
  4. Measure the voltage from the probe of the test lamp to a good ground.
Is the voltage less than the specified value?		 0.3 V Go to Step 18  Go to Step 14 
11 
  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 13  Go to Step 12 
12 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 16  Go to Step 15 
13 
  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 18  Go to Step 17 
14 Test the control circuit of the EGR valve for one of the following conditions:
  • An open
  • A short to ground
  • A short to voltage
  • High resistance

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 23  Go to Step 19 
15 Test the 5-volt reference circuit of the EGR valve position sensor for an open or high resistance. Refer to Circuit Testing andWiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 23  Go to Step 19 
16 Test the low reference circuit of the EGR valve position sensor for an open or high resistance. Refer to Circuit Testing andWiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 23  Go to Step 19 
17 Test the signal circuit of the EGR valve position sensor for an open or high resistance. Refer to Circuit Testing andWiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 23  Go to Step 19 
18 Test the EGR valve for the following:
Did you find and correct the condition?		 - Go to Step 23  Go to Step 21 
19 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 23  Go to Step 22 
20 Repair the ignition 1 voltage circuit of the EGR valve for one of the following conditions:
  • An open
  • A short to ground
  • High resistance

Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 - Go to Step 23  -
21 Replace the EGR valve. Refer to Exhaust Gas Recirculation Valve Replacement .
Did you complete the replacement?		 - Go to Step 23  -
22 Replace the ECM. Refer to Engine Control Module Replacement .
Did you complete the replacement?		 - Go to Step 23  -
23
  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 24 
24 Are there any DTCs that have not been diagnosed? - Go to Diagnostic Trouble Code (DTC) List System OK
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