DTC Confirmation Test

Malfunction is detected when EGR flow is detected under conditions that do not call for EGR. Possible causes are:

• Defective EGR Control (EGRC) solenoid.
• EGR valve stuck open or leaking.
• Defective EGR temperature sensor.
• Defective EGR Control Backpressure Transducer (EGRC-BPT).

Depending on equipment available, use one of the following to set DTC:

• Using Scan Tool
  
  Turn ignition on and select MODE 1 on scan tool. Ensure engine coolant temperature is 14-104°F (-10-40°C) and EGR temperature sensor voltage is less than 4.8 volts. Start engine. Ensure TCS switch is in OFF position. Let engine idle for at least 70 seconds. Turn ignition off and wait at least 5 seconds. Repeat previous steps. Turn ignition on and select MODE 3 on scan tool.
CAUTION: DO NOT use ECM ground terminals when measuring voltage.
• Using MIL
  Turn ignition on. Measure voltage between ground and ECM terminal No. 67 (engine coolant temperature sensor signal) by backprobing. See Figure and Figure . Ensure voltage is 2.7-4.4 volts. Measure voltage between ground and ECM terminal No. 75 (EGR temperature sensor signal) by backprobing. Ensure voltage is less than 4.8 volts. Start engine and let it idle for at least 70 seconds. Turn ignition off and wait at least 5 seconds. Turn ignition on and retrieve DTCs using MIL. See RETRIEVING DIAGNOSTIC TROUBLE CODES USING MIL  under SELF-DIAGNOSTIC SYSTEM.