DTC 32

Code 32 Wiring Diagram:

Code 32 - EGR System Failure:

CIRCUIT DESCRIPTION:
The ECM operates a solenoid to control the Exhaust Gas Recirculation (EGR) valve. This solenoid normally allows for only a small amount of vacuum to pass. By providing a ground path, the ECM energizes the solenoid which then allows enough vacuum to pass to open the EGR valve.
The ECM monitors EGR effectiveness by de-energizing the EGR control solenoid thereby reducing vacuum to the EGR valve diaphragm. With the EGR valve closed, fuel integrator counts will be greater than they were during normal EGR operation. If the change is not within the calibrated window, a Code 32 will be set.
The ECM will check EGR operation when:
- Vehicle speed is above 80 km/h (50 mph)
- Engine vacuum is between 40 and 51 kPa
- No change in throttle position while test is being run

TEST DESCRIPTION
Numbers below refer to circled numbers on the diagnostic chart.
1. With the ignition "ON," engine stopped, the solenoid should not be energized and minimum vacuum should pass to the EGR valve. Grounding the diagnostic terminal will energize the solenoid and allow vacuum to pass to valve.
2. Checks for plugged EGR passages. If passages are plugged, the engine may have severe detonation on acceleration.
3. The vehicle must be driven during this test in order to produce sufficient engine load to operate the EGR. Lightly accelerating (approximately 1/4 throttle) will produce a large and stable enough reading to determine if the ECM is commanding the system ON.

DIAGNOSTIC AIDS
Before replacing the ECM, use an ohmmeter and check the resistance of each ECM controlled relay and solenoid coil. See ECM wiring diagram for relay and pin identification.
Replace any solenoid where resistance is greater than 20 ohms.