Mazda 6 Workshop Manual page 127

Diagnostic procedure
STEP
1 VERIFY FREEZE FRAME DATA HAS BEEN
RECORDED
• Has FREEZE FRAME DATA been recorded?
2 VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Verify related Service Bulletins and/or on-line
repair information availability.
• Is any related repair information available?
3 VERIFY CURRENT SIGNAL STATUS: IS
CONCERN INTERMITTENT OR CONSTANT?
• Connect the WDS or equivalent to the DLC-2.
• Clear the DTC from the PCM memory using
the WDS or equivalent.
• Start the engine.
• Is the same DTC present?
4 IDENTIFY TRIGGER DTC FOR FREEZE FRAME
DATA
• Is DTC P0301, P0302, P0303 or P0304 on
FREEZE FRAME DATA?
5 INSPECT FUEL LINE
• Turn the engine switch off.
• Inspect the fuel lines of the suspected cylinder
for fuel leakage or clogging.
6 VERIFY CURRENT INPUT SIGNAL STATUS
UNDER TROUBLESHOOTING CONDITION
• Access the BOO, ECT, IAT, MAF, RPM, APP,
EGR PS and VSS PIDs using the WDS or
equivalent.
• Is any signal that is far out of specification
when the engine switch is at the ON position
and the engine idles?
7 VERIFY CURRENT INPUT SIGNAL STATUS
UNDER TROUBLE CONDITION
• Inspect the same PIDs as in Step 6 while
simulating the FREEZE FRAME DATA
condition.
• Is there any signal which cause drastic
changes?
8 INSPECT CKP SENSOR
• Inspect the CKP sensor and the pulse wheel.
• Is there any malfunction?
9 INSPECT CMP SENSOR
• Inspect the CMP sensor.
• Is there any malfunction?
10 INSPECT ENGINE COOLANT PASSAGE FOR
ENGINE COOLANT LEAKAGE
• Perform the engine coolant leakage inspection.
• Is there any malfunction?
11 INSPECT ENGINE COMPRESSION
• Inspect the engine compression for the
suspected cylinder.
• Is the engine compression normal?
12 INSPECT FUEL INJECTOR
• Inspect the fuel injector and the related circuit
for the suspected cylinder.
• Is there any malfunction?
ON-BOARD DIAGNOSTIC
INSPECTION
Yes Go to the next step.
No Record the FREEZE FRAME DATA on the repair order,
then go to the next step.
Yes Perform repair or diagnosis according to the available
repair information.
• If the vehicle is not repaired, go to the next step.
No Go to the next step.
Yes Go to the next step.
No Intermittent concern exists.
Perform the "INTERMITTENT CONCERNS
TROUBLESHOOTING".
Yes Go to the next step.
No Go to troubleshooting procedures for the DTC on the
FREEZE FRAME DATA.
Yes Repair or replace the suspected fuel line, then go to Step
13.
No Go to the next step.
Yes Inspect the suspected circuit or part or both according to
the inspection results.
Then go to Step 13.
No Go to the next step.
Yes Inspect suspected circuit or part or both according to the
inspection results.
Then go to Step 13.
No Go to the next step.
Yes Repair or replace the suspected part according to the
inspection results, then go to Step 13.
No Go to the next step.
Yes Repair or replace the suspected part according to the
inspection results, then go to Step 13.
No Go to the next step.
Yes Repair or replace the malfunctioning part according to the
inspection results.
Then go to Step 13.
No Go to the next step.
Yes Go to the next step.
No Overhaul the engine, then go to Step 13.
Yes Repair or replace the suspected part according to the
inspection results, then go to the next step.
No Go to the next step.
ACTION
F2–115
F2