Part 1 of 3

Diagnostic Chart - Part 1 Of 3:

Circuit Schematic:

Notice: Refer to TSB# 96-T-08 for updated information.

PCM/EC DIAGNOSTIC TROUBLE CODE 32 - Part 1 of 3

LINEAR EXHAUST GAS RECIRCULATION (EGR) SYSTEM
The PCM controls the amount of EGR flow by sending a Pulse Width Modulated (PWM) ground signal to a linear EGR module (EGR valve signal modifier module assembly). Since the PCM does not have the capability to control the valve directly the linear EGR module reads the PCM, amplifies the signal to operate the valve.

The EGR solenoid also incorporates a position feedback circuit which sends a signal to the PCM indicating the location of the pintle. This sensor provides closed loop control of EGR as well as diagnostics. When the valve is closed the normal pintle position voltage should be between 0.3 and 1.2 volts.

A Scan tool can be used to monitor the position feedback voltage. This parameter is located in the General Information table. The following parameters can be found in the Fuel and Emission table.

^ % EGR - Indicates the amount of EGR as calculated by the ECM.
^ Desired Position - Precent EGR pintle opening commanded by the PCM.
^ Actual Position - Percent open of the EGR pintle.

DTC PARAMETERS
The PCM constantly monitors the position feedback signal.

DTC 32 will set if:
^ Pintle position voltage is ever below 0.10 volts
^ If actual voltage does not closely match desired voltage after 25 seconds (10% or 26 counts)

TEST DESCRIPTION
^ EGR Solenoid: 7 - 10 ohms [ambient (250°C)]
^ EVAP Canister Purge Solenoid: 20 - 50 ohms
^ Coolant Fan Relay: 70 - 90 ohms
^ A/C Relay: 70 - 90 ohms

^ A shorted or open solenoid, relay or bulb can cause a DTC 26.
^ If one output is bad the PCM will shut down only that QDM output and not the entire quad driver unless the Quad driver reaches its thermal limit (short to voltage). At this time it will turn all four Quad driver outputs off. When the Quad driver cools down it will turn back on and this process will start over.
^ If any corresponding codes have been set (example DTC 26) diagnose that QDM circuit first.
^ A loose or corroded O2 sensor ground (located on engine block below intake manifold left side) will cause and intermittent code 32.