Mazda 6 2002 Workshop Manual page 236

Diagnostic procedure
STEP
1 PERFORM DTC CONFIRMATION PROCEDURE
• Perform DTC CONFIRMATION PROCEDURE.
(See F–66 DTC CONFIRMATION
PROCEDURE.)
• Is same DTC present?
2 CLASSIFY OPEN CIRCUIT OR SHORT TO
GROUND MALFUNCTION
• Disconnect purge solenoid valve tube that is
connected to intake manifold.
• Connect vacuum pump to purge solenoid
valve.
• Pump vacuum pump several times and stop.
• Wait a few seconds.
• Is vacuum maintained?
3 INSPECT PASSAGE CONTROL OF PURGE
SOLENOID VALVE
• Turn ignition key to OFF.
• Disconnect purge solenoid valve connector.
• Pump vacuum pump several times and wait a
few seconds.
• Is vacuum maintained?
4 INSPECT PURGE SOLENOID VALVE
CONNECTOR FOR POOR CONNECTION
• Turn ignition key to OFF.
• Inspect for poor connection (damaged/pulled-
out pins, corrosion, etc.).
• Is there malfunction?
5 INSPECT PURGE SOLENOID VALVE
• Perform purge solenoid valve inspection.
(See F–39 PURGE SOLENOID VALVE
INSPECTION)
• Is purge solenoid valve okay?
6 INSPECT PURGE SOLENOID VALVE POWER
SUPPLY CIRCUIT FOR OPEN CIRCUIT
• Turn ignition key to ON (Engine OFF).
• Measure voltage between purge solenoid valve
connector terminal B and body ground.
• Is voltage B+?
7 INSPECT PCM CONNECTOR FOR POOR
CONNECTION
• Turn ignition key to OFF.
• Disconnect PCM connector.
• Inspect for poor connection (damaged/pulled-
out pins, corrosion, etc.).
• Is there malfunction?
8 INSPECT PURGE SOLENOID VALVE
CONTROL CIRCUIT
• Turn ignition key to ON (Engine OFF).
• Measure voltage between purge solenoid valve
terminal A (harness-side) and body ground.
• Is voltage B+?
9 VERIFY TROUBLESHOOTING OF DTC P0443
COMPLETED
• Make sure to reconnect all disconnected
connectors.
• Perform KOER self-test.
(See F–66 KOEO/KOER
• Is same DTC present?
10 VERIFY AFTER REPAIR PROCEDURE
• Perform “After Repair Procedure”.
(See F–66 AFTER REPAIR
• Is there any DTC present?
ON-BOARD DIAGNOSTIC
INSPECTION
SELF-TEST.)
PROCEDURE.)
Yes Go to net step.
No Intermittent concern eists. Go to INTERMITTENT
CONCERN TROUBLESHOOTING procedure.
(See F–227 INTERMITTENT CONCERN
TROUBLESHOOTING.)
Yes Go to Step 4.
No Go to net step.
Yes Repair or replace harness for short to ground, then go to
Step 9.
No Replace purge solenoid valve, then go to Step 9.
Yes Repair or replace terminal, then go to Step 9.
No Go to net step.
Yes Go to net step.
No Replace purge solenoid valve, then go to Step 9.
Yes Go to net step.
No Repair or replace harness for open, then go to Step 9.
Yes Repair or replace terminal, then go to Step 9.
No Go to net step.
Yes Repair or replace harness for short to power, then go to
net step.
No Inspect for continuity between purge solenoid valve
terminal A (harness-side) and PCM terminal 4U (harness-
side).
• If there is continuity, go to net step.
• If there is no continuity, repair or replace harness for
open, then go to net step.
Yes Replace PCM, then go to net step.
(See F–43 PCM REMOVAL/INSTALLATION.)
No Go to net step.
Yes Go to applicable DTC troubleshooting.
(See F–67 DTC TABLE.)
No Troubleshooting completed.
ACTION
F–139
F