TEST
ACTION
APPLICABILITY
7
Turn the ignition on.
Turn all accessories off.
Disconnect the EGR Solenoid harness connector.
Using a 12-volt Test Light, jumper across the EGR Solenoid harness connector.
With the DRB, actuate the EGR solenoid.
Does the 12-volt test light flash on and off?
All
Yes
→ Inspect the tube(s) for obstructions and damage, repair as neces-
sary. If OK, replace the EGR Solenoid Assembly.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 8
8
Turn the ignition off.
Disconnect the EGR Solenoid harness connector.
Using a 12-volt test light connected to battery voltage, probe the EGR Solenoid
ground circuit in the EGR Solenoid harness connector.
Does the 12-volt test light illuminate brightly?
All
Yes
→ Go To 9
No
→ Repair the open in the EGR Solenoid ground circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
9
Turn the ignition off.
Disconnect the PCM harness connector.
Disconnect the EGR Solenoid harness connector.
Measure the resistance between ground and the EGR Solenoid Control circuit at the
EGR Solenoid harness connector.
Is the resistance below 100 ohms?
All
Yes
→ Repair the short to ground in the EGR Solenoid Control circuirt.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No
→ Go To 10
10
Turn the ignition off.
Disconnect the PCM harness connector.
Disconnect the EGR Solenoid harness connector.
CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMI-
NALS RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Measure the resistance of the EGR Solenoid Control circuit from the EGR Solenoid
harness connector to the appropriate terminal of special tool # 8815.
Is the resistance below 5.0 ohms?
All
Yes
→ Go To 11
No
→ Repair the open in the EGR solenoid control circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
11
NOTE: Before continuing, check the PCM harness connector terminals for
corrosion, damage, or terminal push out. Repair as necessary.
If there are no possible causes remaining, view repair.
All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
145
DRIVEABILITY - NGC
P0401 - EGR SYSTEM PERFORMANCE —
Continued