P0406
P0406-EGR POSITION SENSOR CIRCUIT HIGH
For a complete wiring diagram Refer to the Wiring Information.
- When Monitored:
With the ignition on. Battery voltage greater than 10 volts.
- Set Condition:
EGR position sensor signal is greater than 4.5 volts. One trip Fault.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, select View DTCs. Record DTC and Freeze Frame information.
3. Start the engine and allow it to reach normal operating temperature.
WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in possible serious or fatal injury.
WARNING: The normal operating temperature of the EGR system is very high. Never work around or attempt to service any part of the EGR system until it has cooled. Failure to follow these instructions can result in possible serious or fatal injury.
NOTE: Attempt to operate the vehicle under conditions similar to which the DTC was set.
NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.
4. With a scan tool, select View DTCs.
Is the DTC Active at this time?
Yes
- Go To 2
No
- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition Test.
2. (K34) EGR POSITION SENSOR SIGNAL CIRCUIT SHORTED TO THE (F856) 5-VOLT SUPPLY CIRCUIT
1. Turn the ignition off.
2. Disconnect the EGR Solenoid harness connector.
3. Disconnect the C1 and C2 PCM harness connectors.
4. Measure the resistance between the (K34) EGR Position Sensor Signal circuit and the (F856) 5-volt Supply circuit in the EGR Solenoid harness connector.
Is the resistance below 100 ohms?
Yes
- Repair the short between the (K34) EGR Position Sensor Signal circuit and the (F856) 5-volt Supply circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 3
3. (K34) EGR POSITION SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
1. Ignition on, engine not running.
2. Measure the voltage on the (K34) EGR Sensor Signal circuit in the EGR Solenoid harness connector.
Is there any voltage present?
Yes
- Repair the short to voltage in the (K34) EGR Position Sensor Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 4
4. EGR SOLENOID ASSEMBLY
1. Turn the ignition off.
2. Connect the PCM harness connectors.
3. Ignition on, engine not running.
4. With the scan tool, monitor the EGR Position Sensor voltage.
5. Connect a jumper wire between the (K34) EGR Position Sensor Signal circuit and the (K900) Sensor ground circuit.
NOTE: The sensor voltage should be approximately 0.0 volts (plus or minus.1 volt) with the jumper wire in place.
Does the scan tool display the voltage as described above?
Yes
- Verify that there is good pin to terminal contact in the EGR Solenoid and the Powertrain Control Module connectors. Replace the EGR Valve Assembly if no problems were found with the connectors.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 5
- NOTE: Remove the jumper wire before continuing.
5. (K34) EGR POSITION SENSOR SIGNAL CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the C2 PCM harness connector.
CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install PCM Pinout Box 8815 to perform diagnosis.
3. Measure the resistance of the (K34) EGR Position Sensor Signal circuit from the EGR Solenoid harness connector to the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?
Yes
- Go To 6
No
- Repair the open in the (K34) EGR Position Sensor Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
6. (K900) SENSOR GROUND CIRCUIT OPEN
1. Measure the resistance of the (K900) Sensor ground circuit from the EGR Solenoid harness connector to the appropriate terminal of special tool #8815.
Is the resistance below 30 ohms?
Yes
- Go To 7
No
- Repair the open in the (K900) Sensor ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
7. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Solenoid Assembly and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Solenoid and the Powertrain Control Module connectors.
4. Search for any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.