Mazda 6 Workshop Manual page 225

Diagnostic Procedure
STEP INSPECTION
1 Inspect for the following:
• Fuel quality (such as water contamination,
winter/summer blend)
• Fuel line/fuel filter clogging
• Loose bands on intake-air system
• Cracks on intake-air system parts
• Intake-air system restriction
• Vacuum leakage
• Cooling fan No.1 system operation
Are all items normal?
2 Is the engine overheating?
3 Connect the WDS or equivalent to the DLC-2.
Turn the engine switch to the ON position.
Retrieve any DTC.
Is the DTC displayed?
4 Note
• The following test should be performed on
the vehicles with A/C system. If the
following test cannot be performed due to
the engine stall, go to the next step.
• Go to the next step for the vehicle without
A/C system.
Connect the pressure gauge to the A/C line.
Turn the blower and the A/C switches on.
Is the pressure within specifications?
5 Depress the accelerator pedal slightly.
Crank the engine.
Does the engine start now?
6 Inspect the adjustment of the accelerator
position sensor and idle switch.
Are the accelerator position sensor and the idle
switch adjusted correctly?
7 Inspect the fuel pipe for fuel leakage.
Is any fuel leakage found on fuel pipe?
8 Visually inspect the CKP sensor and the pulse
wheel teeth.
Are the CKP sensor and the pulse wheel teeth
normal?
9 Measure the gap between the CKP sensor and
the pulse wheel teeth.
Specification
1.5—2.5 mm {0.059—0.098 in}
Is the gap within the specification?
TROUBLESHOOTING
RESULTS
Yes Go to the next step.
No Service if necessary
Repeat Step 1.
Yes Go to the symptom troubleshooting "NO.17 COOLING
SYSTEM CONCERNS—OVERHEATING."
No Go to the next step.
Yes DTC is displayed:
Go to the appropriate DTC test.
Communication error message is displayed:
Inspect for the following:
• Open circuit between the PCM control relay and
• Open circuit between the PCM control relay and
• Stuck open PCM control relay
• Open or poor GND circuit (PCM terminal 65, 85,
• Poor connection at vehicle body GND
No No DTC is displayed:
Go to the next step.
Yes Go to the next step.
No A/C is always on:
Go to the symptom troubleshooting "NO.24 A/C
ALWAYS ON OR A/C COMPRESSOR RUNS
CONTINUOUSLY".
Other symptoms:
Inspect for the following:
• Refrigerant charging amount
• Cooling fan No.1 and/or cooling fan No.2 operation
Yes Inspect the idle speed.
No Go to the next step.
Yes Go to the next step.
No Adjust the accelerator position sensor and the idle
switch correctly.
Yes Repair or replace if necessary.
No Go to the next step.
Yes Go to the next step.
No Replace the malfunctioning parts.
Yes Go to the next step.
No Adjust the CKP sensor position.
ACTION
PCM terminal 53 or 79
PCM terminal 69
103 or 104)
F2
F2–213