2002 MAZDA 6 relay

TROUBLESHOOTING
F2–201
F2
End Of Sie
14 Is any engine oil found inside turbocharger
compressor hosing?Yes Wipe oil off of vehicle and install all removed parts in
Step 10. Then, go to next step.
No Turbocharger is okay.
Install all parts removed in Step10.
Then, go to next step.
15 Perform EGR system inspection.
Is EGR system okay?Yes Go to next step.
No Repair or replace malfunctioning part according to
EGR system operation results.
16 Inspect glow system operation.
(See T–19 RELAY INSPECTION)
Is glow system operation normal?Yes Go to next step.
No Repair or replace malfunctioning part according to
glow system operation results.
17 Visually inspect CKP sensor and teeth of pulse
wheel.
Are CKP sensor and teeth of pulse wheel okay?Yes Go to next step.
No Replace malfunctioning parts.
18 Measure gap between CKP sensor and teeth of
pulse wheel.
Specification
1.5—2.5 mm {0.059—0.098 in}
Is gap within specification?Yes Go to next step.
No Adjust CKP sensor position.
19 Visually inspect CMP sensor and teeth of pulse
wheel.
Are CMP sensor and teeth of pulse wheel okay?Yes Inspect following PIDs:
(See F2–65 PCM INSPECTION)
•ECT
•IAT
•MAF
•MAP
•RPM
If PID value is not as specified, repair or replace
malfunctioning parts.
If PID value is okay, go to next step.
No Replace malfunctioning parts.
20 Is engine compression correct?
(See B2–8 COMPRESSION INSPECTION)Yes Go to next step.
No Inspect for following:
•Damaged valve seat
•Worn valve stem and valve guide
•Worn or stuck piston ring
•Worn piston, piston ring or cylinder
•Improper valve timing
Service as necessary.
21 Inspect suction control valve.
(See F2–54 SUCTION CONTROL VALVE
INSPECTION)
Is suction control valve okay?Yes Inspect following:
•Boost sensor
•MAF/IAT sensor
•IAT sensor No.2
•Fuel pressure sensor
•Accelerator position sensor
No Repair supply pump.
(See F2–54 SUPPLY PUMP INSPECTION)
22 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION) STEP INSPECTION RESULTS ACTION

TROUBLESHOOTING
F2–203
F2
3 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Go to next step.
4Note
•The following test should be performed on
the vehicles with A/C system. If the
following test cannot be performed due to
engine stalling, go to next step.
•Go to next step for the vehicle without A/C
system.
Connect pressure gauge to A/C line.
Turn blower and A/C switches on.
Is pressure within specifications?Yes Go to next step
NoA/C is always on:
Go to symptom troubleshooting “NO.24 A/C ALWAYS
ON OR A/C COMPRESSOR RUNS
CONTINUOUSLY”.
Other symptoms:
Inspect following:
•Refrigerant charging amount
•Cooling fan No.1 and/or cooling fan No.2
operation.
5 Access ECT PID.
Drive vehicle while monitoring PID.
Is PID within specification?Yes Go to next step.
No Inspect for coolant leakage, cooling fan No.1 and
cooling fan No.2 operations or thermostat operation.
6 Inspect idle speed.
(See F2–34 IDLE SPEED INSPECTION)
Is idle speed okay?Yes Go to next step.
No Go to symptom troubleshooting “NO.7 SLOW
RETURN TO IDLE”.
7 Perform EGR system inspection.
Is EGR system okay?Yes Go to next step.
No Repair or replace malfunctioning part according to
EGR system operation results.
8 Inspect adjustment of accelerator position
sensor and idle switch.
(See F2–72 ACCELERATOR POSITION
SENSOR INSPECTION)
(See F2–70 IDLE SWITCH INSPECTION)
Are accelerator position sensor and idle switch
adjusted correctly?Yes Go to next step.
No Adjust accelerator position sensor and idle switch
correctly.
(See F2–73 ACCELERATOR POSITION SENSOR
ADJUSTMENT)
(See F2–71 IDLE SWITCH ADJUSTMENT)
9 Is engine compression correct?
(See B2–8 COMPRESSION INSPECTION)Yes Go to next step.
No Inspect for following:
•Damaged valve seat
•Worn valve stem and valve guide
•Worn or stuck piston ring
•Worn piston, piston ring or cylinder
•Improper valve timing
Service as necessary.
10 Inspect fuel injector.
(See F2–56 FUEL INJECTOR INSPECTION)
Is fuel injector okay?Yes Go to next step.
No Repair or replace as necessary.
11 Perform turbocharger inspection.
(See F2–38 TURBOCHARGER INSPECTION)
Is turbocharger okay?Yes Go to next step.
No Replace turbocharger.
12 Inspect guide blade valve operation.
(See F2–229 ENGINE CONTROL SYSTEM
OPERATION INSPECTION)
Is there any problem?Yes Repair or replace as necessary.
No Go to next step.
13 Visually inspect CKP sensor and teeth of pulse
wheel.
Are CKP sensor and teeth of pulse wheel okay?Yes Go to next step.
No Replace malfunctioning parts. STEP INSPECTION RESULTS ACTION

F2–206
TROUBLESHOOTING
3 Connect WDS or equivalent to DLC-2.
Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Go to next step.
4 Inspect for following:
•Fuel quality (e.g.: including water
contamination, winter/summer blend)
•Fuel return line clogging and/or restriction
•Charge air cooler condition (restriction or
damaged)
•Intake-air system restriction
•Exhaust system and/or catalyst converter
restriction
•Vacuum leakage
Are all items okay?Yes Go to next step.
No Service as necessary.
Repeat Step 4.
5 Inspect adjustment of accelerator position
sensor and idle switch.
(See F2–72 ACCELERATOR POSITION
SENSOR INSPECTION)
(See F2–70 IDLE SWITCH INSPECTION)
Are accelerator position sensor and idle switch
adjusted correctly?Yes Go to next step.
No Adjust accelerator position sensor and idle switch
correctly.
(See F2–73 ACCELERATOR POSITION SENSOR
ADJUSTMENT)
(See F2–71 IDLE SWITCH ADJUSTMENT)
6 Inspect adjustment of neutral switch.
(See F2–69 NEUTRAL SWITCH INSPECTION)
Is neutral switch adjusted correctly?Yes Go to next step.
No Adjust neutral switch correctly.
7 Inspect intake shutter valve and VSC valve
operations.
(See F2–229 ENGINE CONTROL SYSTEM
OPERATION INSPECTION)
Is there any problem?Yes Repair or replace as necessary.
No Go to next step.
8 Inspect guide blade valve operation.
(See F2–229 ENGINE CONTROL SYSTEM
OPERATION INSPECTION)
Is there any problem?Yes Repair or replace as necessary.
No Go to next step.
9 Inspect hose bands between following parts:
•Turbocharger compressor housing and air
cleaner
•Turbocharger compressor housing and
charge air cooler
Are hose bands loose?Yes Retighten hose bands.
If concern is resolved, complete inspection.
If concern still exists, go to next step.
No Go to next step.
10 Inspect for improper operation, kinks, clogging or
disconnection on guide blade actuator.
(See F2–229 ENGINE CONTROL SYSTEM
OPERATION INSPECTION)
Is actuator okay?Yes Go to next step.
No Repair or replace as necessary.
If concern is resolved, complete inspection.
If concern still exists, turbocharger is okay.
Go to next step.
11 Remove parts necessary to inspect
turbocharger.
Do not remove turbocharger.
Inspect if turbocharger compressor wheel is
bent, damaged, or interfering with housing on
vehicle.
(See F2–38 TURBOCHARGER INSPECTION)
Is there any problem?Yes Replace turbocharger.
No Go to next step. STEP INSPECTION RESULTS ACTION

TROUBLESHOOTING
F2–207
F2
12 Inspect if turbocharger compressor wheel
locknut is loose or has fallen down inside
turbocharger.
Is there any problem?Yes Replace turbocharger.
No Go to next step.
13 Inspect turbocharger compressor wheel by
hand.
Does wheel turn easily and smoothly?Yes Go to next step.
No Replace turbocharger.
14 Inspect if turbocharger turbine wheel is
damaged, cracked or interfering with housing on
vehicle.
Note
•Inspect all fins on each turbine wheel.
Is there any problem?Yes Replace turbocharger.
No Go to next step.
15 Is any engine oil found inside turbocharger
turbine housing?YesExcessive amount of oil is found:
Replace turbocharger.
Small amount of oil is found:
Wipe oil off of vehicle, then go to next step.
No Go to next step.
16 Is any engine oil found inside turbocharger
compressor hosing?Yes Wipe oil off of vehicle and install all removed parts in
Step 10. Then, go to next step.
No Turbocharger is okay.
Install all parts removed in Step10.
Then, go to next step.
17 Perform EGR system inspection.
Is EGR system okay?Yes Go to next step.
No Repair or replace malfunctioning part according to
EGR system operation results.
18 Inspect EGR water cooler for following:
•Coolant passage clogging/restriction
•Exhaust gas clogging/restriction
Is EGR water cooler okay?Yes Go to next step.
No Service as necessary.
19 Inspect glow system operation.
(See T–19 RELAY INSPECTION)
Is glow system operation normal?Yes Go to next step.
No Repair or replace malfunctioning part according to
glow system operation results.
20 Visually inspect CKP sensor and teeth of pulse
wheel.
Are CKP sensor and teeth of pulse wheel okay?Yes Go to next step.
No Replace malfunctioning parts.
21 Measure gap between CKP sensor and teeth of
pulse wheel.
Specification
1.5—2.5 mm {0.059—0.098 in}
Is gap within specification?Yes Go to next step.
No Adjust CKP sensor position.
22 Visually inspect CMP sensor and teeth of pulse
wheel.
Are CMP sensor and teeth of pulse wheel okay?Yes Inspect following PIDs:
(See F2–65 PCM INSPECTION)
•ECT
•IAT
•MAF
•MAP
•RPM
•VSS
If PID value is not as specified, repair or replace
malfunctioning parts.
If PID value is okay, go to next step.
No Replace malfunctioning parts.
23 Inspect fuel pressure sensor.
(See F2–79 FUEL PRESSURE SENSOR
INSPECTION)
Is fuel pressure okay?Yes Go to next step.
No Replace common rail.
24 Inspect suction control valve.
(See F2–54 SUCTION CONTROL VALVE
INSPECTION)
Is suction control valve okay?Yes Go to next step.
No Repair supply pump.
(See F2–54 SUPPLY PUMP INSPECTION) STEP INSPECTION RESULTS ACTION

F2–210
TROUBLESHOOTING
End Of SieNO.17 COOLING SYSTEM CONCERNS-OVERHEATINGA6E408018881219
Diagnostic Procedure
17
COOLING SYSTEM CONCERNS-OVERHEATING
DESCRIPTION•Engine runs at higher than normal temperature/overheats.
POSSIBLE
CAUSE•Cooling fan No.2 malfunction
•Cooling fan No.1 malfunction
•Low drive belt tension
•Drive belt damage
•Improper coolant level
•Thermostat malfunction
•Radiator clogging
•Improper water/anti-freeze mixture
•Improper or damaged radiator cap
•Radiator hose damage
•Coolant leakage (engine internal, turbocharger, external)
•A/C system malfunction
•EGR system malfunction
•Coolant heater system malfunction
STEP INSPECTION RESULTS ACTION
1 Inspect following:
•Engine coolant level
•Coolant leakage (around heater unit in
passenger compartment, coolant hoses and/
or radiator, and around coolant heater unit.)
•Water and anti-freeze mixture
•Radiator condition
•Collapsed or restricted radiator hoses
•Radiator pressure cap
•Drive belt tension
•Drive belt
•Fan rotational direction
Are all items okay?Yes Go to next step.
No Service as necessary.
Repeat Step 1.
2 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Go to next step.

TROUBLESHOOTING
F2–211
F2
End Of Sie
3Note
•The following test should be performed on
the vehicles with A/C system. Go to next
step for vehicles without A/C system
Start engine and run it at idle speed.
Turn A/C switch off.
Does A/C compressor disengaged?Yes Go to next step.
No Go to symptom troubleshooting “NO.24 A/C ALWAYS
ON OR A/C COMPRESSOR RUNS
CONTINUOUSLY”.
4 Start engine and run it at idle speed.
Turn A/C switch on if equipped.
Do cooling fan No.1 and/or cooling fan No.2
operate?Yes Go to next step.
NoCooling fan No.1 does not operate:
Inspect for following:
•Cooling fan relay No.1 is stuck open
•Cooling fan motor No.1 malfunction
•Cooling fan motor No.1 GND open
•Open circuit between cooling fan motor No.1 and
relay
•Open circuit between cooling fan relay No.1 and
PCM terminal 102
•Open battery power circuit of cooling fan relay
No.1
Cooling fan No.2 does not operate:
Inspect for following:
•Cooling fan relay No.2 is stuck open
•Cooling fan motor No.2 malfunction
•Cooling fan motor No.2 GND open
•Open circuit between Cooling fan motor No.2 and
relay
•Open circuit between Cooling fan relay No.2 and
PCM terminal 76
•Open battery power circuit of Cooling fan relay
No.2
5 Is drive belt okay? Yes Go to next step.
No Replace drive belt.
6 Perform EGR system inspection.
Is EGR system okay?Yes Go to next step.
No Repair or replace malfunctioning part according to
EGR system operation results.
7 Perform coolant heater system inspection.
(See E–10 THERMOSTAT INSPECTION)
Is coolant heater system okay?Yes Go to next step.
No Repair or replace malfunctioning part according to
coolant heater system operation results.
8 Cool down engine.
Remove thermostat and inspect operation.
Is thermostat okay?Yes Thermostat is okay.
Inspect cylinder block for leakage or blockage.
No Replace thermostat.
9 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION) STEP INSPECTION RESULTS ACTION

F2–212
TROUBLESHOOTING
NO.18 COOLING SYSTEM CONCERNS-RUNS COLDA6E408018881220
Diagnostic Procedure
End Of Sie
18 COOLING SYSTEM CONCERNS-RUNS COLD
DESCRIPTION•Engine takes excessive period for reaching normal operating temperature.
POSSIBLE
CAUSE•Thermostat malfunction
•Cooling fan No.2 system malfunction
•Cooling fan No.1 system malfunction
•Coolant heater system malfunction
STEP INSPECTION RESULTS ACTION
1 Is customer complaint “Lack of passenger
compartment heat”?Yes Inspect A/C heater system.
No Go to next step.
2 Does engine speed continue at fast idle? Yes Go to symptom troubleshooting “NO.7 SLOW
RETURN TO IDLE”.
No Go to next step.
3 Connect WDS or equivalent to DLC-2.
Access ECT PID.
Inspect for both ECT PID and temperature
gauge on instrument cluster readings.
Is ECT PID same as temperature gauge
reading?Yes Go to next step.
No If temperature gauge on instrument cluster indicates
normal range but ECT PID is not same as temperature
gauge reading, inspect ECT sensor.
If temperature gauge on instrument cluster indicates
cold range but ECT PID is normal, inspect
temperature gauge and heat gauge unit.
4 Remove thermostat and inspect operation.
(See E–9 THERMOSTAT REMOVAL/
INSTALLATION)
(See E–10 THERMOSTAT INSPECTION)
Is thermostat okay?Yes Go to next step.
No Replace thermostat.
5 Inspect cooling fan No.1 and cooling fan No.2
operations.
If both or either fan operate normally, inspect for
following:
•Cooling fan relay No.2 is stuck closed
•Short to GND between cooling fan relay No.2
and PCM terminal 76
•Circuit between cooling fan relay No.2 and
fan motor short to battery supply line
•Cooling fan relay No.1 is stuck closed
•Short to GND between cooling fan relay No.1
and PCM terminal 102
•Circuit between cooling fan relay No.1 and
fan motor short to battery supply line
•Short to GND between A/C switch and PCM
terminal 84
Are all circuits okay?Yes Perform coolant heater system inspection.
Repair or replace malfunctioning part according to
coolant heater system operation results.
No Repair or replace as necessary.
6 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. (See F2–64 PCM REMOVAL/INSTALLATION)

TROUBLESHOOTING
F2–213
F2
NO.19 EXCESSIVE BLACK SMOKEA6E408018881221
Diagnostic Procedure
19 EXCESSIVE BLACK SMOKE
DESCRIPTION•Excessive black smoke is observed in exhaust gas.
POSSIBLE
CAUSE•Intake-air system clogging or restriction
•Air leakage from Intake-air system
•Incorrect fuel injection timing
•Erratic signal from CKP sensor
•Fuel pressure sensor or related circuit malfunction
•Boost sensor or related circuit malfunction
•IAT sensor No.2 or related circuit malfunction
•Fuel injector malfunction
•Excessive fuel pressure
•Suction control valve malfunction (built-in supply pump)
•Fuel line clogging or restriction
•Fuel pressure limiter malfunction (built-in common rail)
•Low engine compression
•Improper valve timing
•Base engine malfunction
•EGR system malfunction
•Variable boost control (VBC) system malfunction
•Vacuum leakage
•Turbocharger malfunction
•Charge air cooler malfunction
•Intake shutter valve malfunction
•Variable swirl control (VSC) system malfunction
•VSC valve malfunction
•IDM or related circuit malfunction
•Exhaust system and/or catalyst converter restriction or clogging
Warning
The following troubleshooting flow chart contains the fuel system diagnosis and repair
procedures. Read the following warnings before performing the fuel system services:
•Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep
sparks and flames away from fuel.
•Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injury or death
and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE
REPAIR PROCEDURE” and “AFTER REPAIR PROCEDURE” described in this manual.
STEP INSPECTION RESULTS ACTION
1 Inspect for following:
•Intake-air system clogging or restriction
•Exhaust system and/or catalyst converter
restriction or clogging
•Charge air cooler condition (restriction or
damaged)
Are all items okay?Yes Go to next step.
No Service as necessary.
Repeat Step 1.
2 Perform self-test function using WDS or
equivalent.
Turn engine switch to ON.
Retrieve any DTC.
Is DTC displayed?YesDTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:
•Open circuit between PCM control relay and PCM
terminal 53 or 79
•Open circuit PCM control relay and PCM terminal
69
•PCM control relay stuck open
•Open or poor GND circuit (PCM terminal 65, 85,
103 or 104)
•Poor connection vehicle body GND
NoNo DTC is displayed:
Go to next step.
3 Does any other symptom exist? Yes Go to appropriate flowchart.
No Go to next step.
4 Inspect for air cleaner element for clogging.
Is air cleaner element okay?Yes Go to next step.
No Repair or replace air cleaner element.