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Diagnostic Aids

Prior to replacing PCM, check resistance of all PCM-controlled solenoids and relays. Replace any with a resistance value less than 20 ohms.

Fig 1: Code 32 Schematic (4.3L C, G, K & P Series W/4L80-E Trans.) EGR System Error
G91J13747
Fig 2: Code 32 Flow Chart (4.3L C, G, K & P Series W/4L80-E Trans.) EGR System Error
G91B07323


Prior to replacing PCM, check resistance of all PCM-controlled solenoids and relays. Replace any with a resistance value less than 20 ohms.

Fig 1: Code 32 Schematic (All Engines W/4L80-E Trans. Except 4.3L) EGR System Error
G91D13782
Fig 2: Code 32 Flow Chart (All Engines W/4L80-E Trans. Except 4.3L) EGR System Error
G91C13781


Prior to replacing PCM, check resistance of all PCM-controlled solenoids and relays. Replace any with a resistance value less than 20 ohms.

Fig 1: Code 32 Schematic (2.5L, 4.3L Non-Turbo & S & T 5.0L & 5.7L) EGR System Error
G91I13746
Fig 2: Code 32 Schematic (2.8L, 4.3L S & T Series & 7.4L) EGR System Error
G91H13745
Fig 3: Code 32 Flow Chart (All W/O 4L80-E Trans. Except 3.1L & 4.3L Turbo) EGR System Error
G91J13671


Vacuum switch in the EGR solenoid is not used. If EGR valve sticks open, a rough idle will result. If EGR solenoid vent filter becomes plugged, EGR valve will remain open or close slowly. An inoperative check valve in the ported vacuum supply line will result in faulty EGR system operation.

Fig 1: Code 32 Schematic (4.3L) EGR System Error
G91F13743
Fig 2: Code 32 Flow Chart (4.3L) EGR System Error
G91I13712