Mazda 2002 6 - Page 249

F–120
ON-BOARD DIAGNOSTIC
End Of Sie
2 VERIFY RELATED PENDING CODE OR
STORED DTCS
• Turn ignition key to OFF, then ON (Engine
OFF).
• Verify related pending code or stored DTCs.
• Is other DTCs present?
Yes Go to appropriate DTC troubleshooting procedures.
No If drive ability concern is present, go to Step 8.
If not, go to next step.
3 IDENTIFY TRIGGER DTC FOR FREEZE FRAME
DATA
• Is DTC P0172 on FREEZE FRAME DATA?
Yes Go to next step.
No Go to troubleshooting procedures for DTC on FREEZE
FRAME DATA.
4 VERIFY CURRENT INPUT SIGNAL STATUS
(IGNITION KEY TO ON/IDLE)
• Access ECT, MAF, TP and VSS PIDs using
WDS or equivalent.
• Is there any signal that is far out of
specification when ignition key is ON and
engine runs?
Yes Inspect suspected sensor and excessive resistance in
related wiring harnesses. Repair or replace if necessary.
Then go to Step 10.
No Go to next step.
5 VERIFY CURRENT INPUT SIGNAL STATUS
UNDER TROUBLE CONDITION
• Inspect PID data while simulating FREEZE
FRAME DATA condition.
• Is there any input signal which causes drastic
changes?
Yes Inspect suspected sensor and related wiring harnesses,
and repair or replace it. Then go to Step 10.
No Go to next step.
6 VERIFY CURRENT INPUT SIGNAL STATUS OF
FRONT HO2S
• Access O2S11 PID using WDS or equivalent.
• Verify PID while racing engine (in PARK (ATX)
or NEUTRAL (MTX)).
• Is PID reading okay?
— Above 0.55 V when accelerator pedal is
suddenly depress (rich condition).
— Below 0.55 V just after release of
accelerator pedal (lean condition)
Yes Go to next step.
No Replace suspected front HO2S.
Then go to Step 10.
7 INSPECT FUEL LINE PRESSURE
• Turn ignition key to OFF.
• Inspect fuel line pressure while engine running.
(See F–20 FUEL LINE PRESSURE
INSPECTION.)
• Is fuel line pressure okay?
Yes Go to next step.
No Replace fuel pump unit, then go to Step 10.
8 INSPECT PURGE SOLENOID VALVE FOR
STUCK OPEN
• Turn ignition key to OFF.
• Disconnect both hoses from purge solenoid
valve.
• Blow air through purge solenoid valve.
• Does air blow through?
Yes Replace purge solenoid valve.
Then go to Step 10.
No Go to next step.
9 INSPECT PCV VALVE OPERATION
• Inspect PCV valve operation.
(See F–41 PCV VALVE INSPECTION.)
• Is PCV valve okay?
Yes Go to next step.
No Replace PCV valve, then go to next step.
10 VERIFY TROUBLESHOOTING OF DTC P0172
COMPLETED
• Make sure to reconnect all disconnected
connectors.
• Turn ignition key to ON (Engine OFF).
• Clear DTC from memory using WDS or
equivalent.
• Perform KOER self-test.
(See F–66 KOEO/KOER SELF-TEST.)
• Is same DTC present?
Yes Replace PCM, then go to next step.
(See F–43 PCM REMOVAL/INSTALLATION.)
No Go to next step.
11 VERIFY AFTER REPAIR PROCEDURE
• Perform “After Repair Procedure”.
(See F–66 AFTER REPAIR PROCEDURE.)
• Is there any DTC present?
Yes Go to applicable DTC troubleshooting.
(See F–67 DTC TABLE.)
No Troubleshooting completed.
STEP INSPECTION ACTION