E032

Code EO32 - Exhaust Gas Recirculation System Fault:

Wiring Diagram for Code E032 - Exhaust Gas Recirculation System Fault:

CODE E032 - EGR SYSTEM FAULT

Circuit Description:

The EGR Vacuum Control is operated by an Electronic Vacuum Regulator Valve (EVRV). The EVRV is comprised of an EGR Vacuum Control Solenoid and a EGR Diagnostic Vacuum Switch.

The EGR Solenoid is Pulse Width Modulated by the ECM and controls the vacuum to the EGR valve. The Solenoid is vented and is equipped with a filter.

The normally open EGR Diagnostic Vacuum Switch monitors the vacuum to the EGR Valve and signals the ECM when control vacuum is applied to the valve (switch closes). The ECM will not energize the solenoid in "Park", "Neutral", or at idle.

The ECM cycles the EGR valve "ON" and "OFF" (Pulse Width Modulation). For this reason, the EGR valve is never continously open but always "pulsed" which may be monitored by observing the ECM input EI60 (EVRV Switch) during normal EGR operation. "HI" indicates the EGR is off and "LO" indicates it is on.

Code E032 will set if the vacuum switch closes at idle, or if it does not close under load (less than WOT).

a. Engine running.
b. Code E033 or E034 not present
c. Coolant temperature above 42.5°C (108°F).
d. LV8 reading less than 144 cts.
e. Conditions exist over 5 seconds.




Test Description: The following numbered steps correspond with the step numbers on diagnostic charts.

1. EI60 displays the condition of the EGR diagnostic switch. In park or neutral, the display should read "HI" (open switch).

2. Under moderate engine load, the display will switch from "HI" to "LO".

3. Jumping terminals "B" to "C" with a test light will verify the integrity of the ECM wiring and check for proper ECM operation.

4. Checks the integrity of the 12V feed and ground circuits. If these circuits check OK, the fault is in the EVRV/EGR Control Solenoid.

5. If "LO" was displayed at idle, disconnect the EVRV harness. If display remains "LO", the fault is either a short to ground in CKT 357 or the ECM.

6. If the EI60 display switches from "LO" to "HI" when the EVRV is disconnected, the fault is either in the EVRV/EGR Solenoid, CKT 435 or the ECM. Probing at terminal "B" will further isolate the fault. If the test light is on, disconnect ECM A-B connector before checking CKT 435 for a short to ground since the short could be inside the ECM.

Diagnostic Aids:

An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation.

Check For:

a. Poor Connection or Damaged Harness - Inspect ECM harness connectors for backed our terminal "D9", improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection and damaged harness.

b. Intermittent Test - If connections and harness checks out ok, monitor EI60 (EVRV Switch) display while moving related connectors and wiring harness. If the failure is induced, the "EVRV Switch" display will abruptly change. This will help to isolate the location of the malfunction.