DTC 32

Code 32 Chart:

Code 32 Wiring Diagram:

CIRCUIT DESCRIPTION:

The Exhaust Gas Recirculation (EGR) vacuum control uses an Electronic Control Module (ECM) controlled Solenoid. The Solenoid is normally closed and the vacuum source is a ported signal. The ECM will turn the EGR "ON" and "OFF" (Duty Cycle) by grounding CKT 435. The duty cycle is calculated by the ECM based on information from the coolant and Mass Air Flow (MAF) Sensor and engine rpm. The duty cycle should be 0% (no EGR) when in Park or Neutral, Throttle Position Sensor (TPS) input below a specified value, or TPS indicating Wide Open Throttle (WOT). With the ignition "ON", engine stopped, the EGR solenoid is de-energized unless the diagnostic terminal is grounded. Code 32 means that the EGR vacuum diagnostic switch was closed during start-up, or that the switch was not detected closed under the following conditions:

^ Coolant temperature greater than 80~C (176~F)
^ EGR duty cycle commanded by the ECM is greater than 55%
^ TPS less than half throttle, but not at idle
^ All conditions above must be met for 5 seconds
^ If the switch is detected closed during start-up, or, if the switch is detected open when the above conditions are met, the "SERVICE ENGINE SOON" (SES) light will remain "ON" unless the switch changes state.

NOTE: Because of all the possible color code combinations used on electrical wiring diagrams, always refer to ECM CONNECTOR IDENTIFICATION under ELECTRICAL AND ELECTRONIC WIRING DIAGRAMS for correct color code identification of circuit.

TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.

1. If the first step caused Code 32 to set, then the ECM has recognized a closed vacuum switch on start-up. This test will determine whether the EGR vacuum diagnostic switch is the cause or if the wiring or the ECM is the cause.

2. With the ignition "ON", the solenoid should not be energized and vacuum should not pass to the EGR valve.

3. To this point the EGR solenoid and valve are OK and the following check will check the diagnostic vacuum switch portion of the system.

4. The diagnostic switch should close at about 2" of vacuum, With vacuum applied, the switch should close and resistance go to near zero ohms and the vacuum should hold.