2002 MAZDA 6 Workshop Manual Suplement

TROUBLESHOOTING
F1–57
F1
ENGINE SYMPTOM TROUBLESHOOTINGA6E398018881201•Confirm trouble symptom using the following diagnostic index, then go to appropriate troubleshooting chart.
Diagnostic Index
End Of Sie
TROUBLESHOOTING
No. TROUBLESHOOTING ITEM DESCRIPTION
1 Melting of main or other fuses—
2 MIL illuminates MIL is illuminated incorrectly.
3 Will not crank Starter does not work.
4Hard to start/long crank/erratic start/erratic
crankStarter cranks engine at normal speed but engine requires excessive
cranking time before starting.
5 Engine stalls. After start/at idle Engine stops unexpectedly at idle and/or after start.
6 Cranks normally but will not start Starter cranks engine at normal speed but engine will not run.
7 Slow return to idle Engine takes more time than normal to return to idle speed.
8 Engine runs rough/rolling idleEngine speed fluctuates between specified idle speed and lower
speed and engine shakes excessively.
9 Fast idle/runs onEngine speed continues at fast idle after warm-up.
Engine runs after ignition switch is turned to off.
10 Low idle/stalls during decelerationEngine stops unexpectedly at beginning of deceleration or recovery
from deceleration.
11Engine stalls/quits. Acceleration/cruiseEngine stops unexpectedly at beginning of acceleration or during
acceleration.
Engine stops unexpectedly while cruising.
Engine runs rough. Acceleration/cruise Engine speed fluctuates during acceleration or cruising.
Misses Acceleration/cruise Engine misses during acceleration or cruising.
Buck/jerkAcceleration/cruise/
decelerationVehicle bucks/jerks during acceleration, cruising, or deceleration.
Hesitation/stumble Acceleration Momentary pause at beginning of acceleration or during acceleration
Surges Acceleration/cruise Momentary minor irregularity in engine output
12 Lack/loss of power Acceleration/cruisePerformance is poor under load.
(e.g., power down when climbing hills)
13 Knocking/pinging Acceleration/cruiseSound is produced when air/fuel mixture is ignited by something other
than spark plug. (e.g., hot spot in combustion chamber)
14 Poor fuel economy Fuel economy is unsatisfactory.
15 Emission compliance Fails emissions test.
16 High oil consumption/leakage Oil consumption is excessive.
17Cooling system
concernsOverheating Engine runs at higher than normal temperature/overheats.
18Cooling system
concernsRuns cold Engine does not reach normal operating temperature.
19 Exhaust smoke Blue, black, or white smoke from exhaust system
20 Fuel odor (in engine compartment) Gasoline fuel smell or visible leakage
21 Engine noise Engine noise from under hood
22 Vibration concerns (engine) Vibration from under hood or driveline
23 A/C does not work sufficiently.A/C compressor magnetic clutch does not engage when A/C is turned
on.
24A/C is always on or A/C compressor runs
continuously.A/C compressor magnetic clutch does not disengage.
25 A/C is not cut off under WOT conditions. A/C compressor magnetic clutch does not disengage under WOT.
26 Exhaust sulphur smell Rotten egg smell (sulphur) from exhaust
27 Constant voltage Incorrect constant voltage
28 Spark plug condition Incorrect spark plug condition
29 ATX concernsUpshift/downshift/
engagementATX concerns not related to engine performance

F1–58
TROUBLESHOOTING
QUICK DIAGNOSTIC CHARTA6E398018881202
X: Applicable
Possible factor
Troubleshooting item
Starter motor malfunction (Mechanical or electrical)
Starter circuit including ignition switch is open.
Starter interlock switch malfunction (MTX with starter
interlock system)
Improper engine oil level
Low or dead battery
Charging system malfunction
Improper engine compression
Improper valve timing
Hydrolocked engine
Improper engine oil viscosity
Improper dipstick
Base engine malfunction
Drive plate or flywheel are seized.
Improper tension or damaged drive belts
Improper engine coolant level
Water and anti-freeze mixture is improper.
Cooling system malfunction (Radiator, hoses,
overflow system, thermostat, etc.)
Cooling fan system malfunction
Engine or transaxle mounts are improperly installed.
Cooling fan or condenser fan seat are improper.
Accelerator cable free play misadjustment
Cruise control cable misadjustment
Fuel quality
1 Melting of main or other fuses2 MIL illuminates x x x x x x x3 Will not crank4 Hard to start/long crank/erratic start/erratic
crankx
5 Engine stalls. After start/at idle x x x x6 Cranks normally but will not start x x x x7 Slow return to idlex8 Engine runs rough/rolling idle x x x9 Fast idle/runs onxx10 Low idle/stalls during decelerationEngine stalls/quits. Acceleration/cruise x x xEngine runs rough. Acceleration/cruise x x xMissesAcceleration/cruise x x xBuck/jerk Acceleration/cruise/
decelerationxx x
Hesitation/stumble Acceleration x x x
11
Surges Acceleration/cruis
exx x12 Lack/loss of powerAcceleration/cruisexx x13 Knocking/pingingAcceleration/cruisexx14 Poor fuel economy x x x x x x15 Emission compliance x x x x16 High oil consumption/leakage x x x17 Cooling system concerns Overheatingxx x x x18 Cooling system concernsRuns cold x x19 Exhaust smoke x x x20 Fuel odor (in engine compartment)21 Engine noise x x x22 Vibration concerns (engine) x x x23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smellx27 Constant voltage28 Spark plug condition x x29 ATX concernsUpshift/downshift
engagementSee Section K, TROUBLESHOOTING
A6E39802001

TROUBLESHOOTING
F1–59
F1
X: Applicable
Possible factor
Troubleshooting itemVariable valve timing system malfunction (L3 engine
model)
VICS malfunction
Engine overheating
Air cleaner element clogging or restriction
Air leakage from intake-air system (Loose tubes,
cracks, gaskets breakage)
IAC valve improper operation
Throttle body malfunction
VICS malfunction (L3 engine model)
VACS malfunction (L3 engine model)
Vacuum leakage (Vacuum hose damage, misrouting)
Ignition coil malfunction (e.g. open, short or cracks)
Initial ignition timing misadjustment (CKP sensor &
crankshaft pulley misadjustment)
Spark plug malfunction
High-tension leads malfunction (Cracks, open, low
resistance)
CKP sensor is damaged. (e.g. open or short circuits )
Crankshaft pulley is damaged
Improper gap between CKP sensor and crankshaft
Fuel pump malfunction (Mechanically or electrically)
Pressure regulator malfunction
Fuel hoses restriction or clogging
1 Melting of main or other fuses2 MIL illuminates x x x x x3 Will not crank4 Hard to start/long crank/erratic start/erratic
crankx x x x x x xxxxxx
5 Engine stalls. x x x x x xxxxxxxxxxx6 Cranks normally but will not start x x x x xxxxxxxxxxx7 Slow return to idle x8 Engine runs rough/rolling idle x x x x x x x x xxxxxxx9 Fast idle/runs on x x10 Low idle/stalls during deceleration x x xEngine stalls/quits. Acceleration/cruise x x x x x x x x xxxxxxxEngine runs rough. Acceleration/cruise x x x x x x x x xxxxxxxMissesAcceleration/cruise x x x x x x x x xxxxxxxBuck/jerk Acceleration/cruise/dece
lerationxxx x xx x x x xxxxxx
Hesitation/stumble Acceleration x x x x x x x x xxxxxxx
11
Surges Acceleration/cruise x x x x x x x x xxxxxxx
12 Lack/loss of powerAcceleration/cruise x x x x x x x x xxxxxxx13 Knocking/pingingAcceleration/cruise x x x14 Poor fuel economy x x x x x x x15 Emission compliance x x x x x x x x x16 High oil consumption/leakage17 Cooling system
concernsOverheating
18 Cooling system
concernsRuns cold
19 Exhaust smoke x x x x x x20 Fuel odor (in engine compartment)x21 Engine noise x x x22 Vibration concerns (engine)23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smell x x x x27 Constant voltage28 Spark plug condition x x x x x x29 ATX concernsUpshift/downshift
engagementSee Section K, TROUBLESHOOTING
A6E39802002

F1–60
TROUBLESHOOTING
X: Applicable
Possible factor
Troubleshooting item
Injectors malfunction (Leakage or clogging, inope-rative
Fuel leakage from fuel system (including insulator,
injector O-ring)
Fuel filters restriction or clogging
CMP sensor is damaged. (e.g. open or short circuit)
Camshaft is damaged.
Improper air/fuel mixture ratio control
Exhaust system restriction or clogging
Catalytic converter malfunction
EGR system malfunction (Unleaded gasoline models)
EVAP control system malfunction
PCV valve malfunction
Constant voltage supply circuit malfunction
Main relay malfunction (Mechanically or electrically)
ECT sensor malfunction
TR sensor misadjustment (ATX)
TR sensor malfunction (ATX)
Break switch and related circuit malfunction
Manifold absolute pressure sensor and related circuit
malfunction
HO2S and related circuit malfunction (Unleaded
gasoline models)
Variable resistor misadjustment (Leaded gasoline
models)
Improper electrically controlled 4WD system operation
1 Melting of main or other fuses2 MIL illuminates x x x x x x x3 Will not crankxx4 Hard to start/long crank/erratic start/erratic
crankx xx xxx x
5 Engine stalls. After start/at idle x x x x x x x x x6 Cranks normally but will not start x x x xxxxxx x7 Slow return to idlex8 Engine runs rough/rolling idle xxxxxx xxx x9 Fast idle/runs onx10 Low idle/stalls during deceleration x x x x xEngine stalls/quits.Acceleration/cruisex xxxxx xxxxx xEngine runs rough. Acceleration/cruisex xxxxx xxxxx xMissesAcceleration/cruisex xxxxx xxxxx xBuck/jerk Acceleration/cruise/
decelerationx xxxxx xxxxx x
Hesitation/stumble Acceleration xxxxxx xxxxx x
11
Surges Acceleration/cruise xxxxxx xxxxx x
12 Lack/loss of power Acceleration/cruise x x x x x x x x13 Knocking/pingingAcceleration/cruise x14 Poor fuel economy x x x x x x15 Emission compliancexxxxxxxxx x16 High oil consumption/leakage x17 Cooling system concerns Overheating18 Cooling system concernsRuns cold19 Exhaust smoke x x20 Fuel odor (in engine compartment) x x21 Engine noise22 Vibration concerns (engine)x23 A/C does not work sufficiently.24 A/C is always on or A/C compressor runs
continuously.
25 A/C is not cut off under WOT conditions.26 Exhaust sulfur smell x x27 Constant voltage x x x x x28 Spark plug condition x x x x29 ATX concernsUpshift/downshift/en
gagementSee Section K, TROUBLESHOOTING
A6E39802003

TROUBLESHOOTING
F1–61
F1
End Of Sie
X: Applicable
Possible factor
Troubleshooting itemIAT sensor and related circuit malfunction
Barometric pressure sensor malfunction
Neutral or clutch switch and related circuit
malfunction (MTX)
MAF sensor and related circuit malfunction
Knock sensor and related circuit malfunction
TP sensor and related circuit malfunction
TP sensor misadjustment (including looseness)
P/S pressure switch and related circuit
malfunction
Improper refrigerant charging amount
A/C relay (A/C control signal circuit malfunction
A/C compressor magnetic clutch malfunction
Condenser fan system malfunction
Improper load signal input
Clutch slippage
ATX related parts malfunction
VSS and related circuit malfunction
Improper ATF level
Brake dragging
Loose parts
Improper balance of wheels and tires
Drive line malfunction
Suspension malfunction
PATS operating (if equipped)
1 Melting of main or other fuses2 MIL illuminates x x x x x x x x3 Will not crankx4 Hard to start/long crank/erratic
start/erratic crankx
5 Engine stalls. After start/at idle x x x x6 Cranks normally but will not startx7 Slow return to idle8 Engine runs rough/rolling idle x x x x x x9 Fast idle/runs onx10 Low idle/stalls during deceleration x x x x x xEngine stalls/quits.Acceleration/cruisex x xx xx xxxEngine runs rough. Acceleration/cruisex x xx xx xxxMissesAcceleration/cruisex xx xx xxxBuck/jerk Acceleration/cruise
/decelerationx xx xx xxx
Hesitation/stumble Acceleration x x x x x x x x x
11
Surges Acceleration/cruise x x x x x x x x
12 Lack/loss of power Acceleration/cruise x x x x x x x x13 Knocking/pingingAcceleration/cruise x x x14 Poor fuel economy x x x x x15 Emission compliance x16 High oil consumption/leakage17 Cooling system
concernsOverheating x x x
18 Cooling system
concernsRuns cold x
19 Exhaust smoke20 Fuel odor (in engine compartment)21 Engine noisex22 Vibration concerns (engine)xxxx23 A/C does not work sufficiently. x x x24 A/C is always on or A/C compressorruns continuously.xx25 A/C is not cut off under WOT conditions x x26 Exhaust sulfur smell27 Constant voltage x x x x x x28 Spark plug condition x x29 ATX concernsUpshift/downshift/e
ngagementSee Section K, TROUBLESHOOTING
A6E39802004

F1–62
TROUBLESHOOTING
NO.14 POOR FUEL ECONOMYA6E398018881203
Diagnostic procedure
14 POOR FUEL ECONOMY
DESCRIPTIONFuel economy is unsatisfactory.
POSSIBLE CAUSE•Contaminated air cleaner element
•VIS malfunction (if equipped)
•Engine cooling system malfunction
•Improper ATF level (ATX)
•Weak spark
•Poor fuel quality
•Erratic or no signal from CMP sensor
•Clutch slippage (MTX)
•VTCS malfunction
•Improper variable valve timing control system operation (if equipped)
•Improper coolant level
•Inadequate fuel pressure
•Spark plug malfunction
•PCV valve malfunction
•Brake dragging
•Improper valve timing due to jumping out of timing belt
•Contaminated MAF sensor
•Improper engine compression
•Exhaust system clogging
•Improper electrically controlled 4WD system operation
Warning
The following troubleshooting flow chart contains fuel system diagnosis and repair
procedures. Read following warnings before performing 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 injuries 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.
Caution
•Disconnecting/connecting quick release connector without cleaning it may possibly cause
damage to fuel pipe and quick release connector. Always clean quick release connector
joint area before disconnecting/connecting, and make sure that it is free of foreign material.
STEP INSPECTION RESULTS ACTION
1 Inspect for following:
•Air cleaner element for contamination
•ATF level
•Fuel quality
•Coolant level
•Brake dragging
•Clutch slippage
Are all items okay?Yes Go to next step.
No Service as necessary.
Repeat Step 1.
2 Connect WDS or equivalent to DLC-2.
Retrieve any continuous memory, KOEO and
KOER DTCs.
Are there any DTCs displayed?YesDTC is displayed:
Go to appropriate DTC test.
NoNo DTC is displayed:
Go to next step.
3 Access ECT PID.
Drive vehicle while monitoring PID.
(See F1–33 PCM INSPECTION (4WD).)
Is PID within specification?Yes Go to next step.
No Inspect for coolant leakage, cooling fan and condenser
fan operations or thermostat operation.

TROUBLESHOOTING
F1–63
F1
End Of Sie
4 Is strong blue spark visible at each disconnected
high-tension lead while cranking engine?Yes Inspect for following:
•Spark plugs malfunction
•CMP sensor is improperly installed.
•Trigger wheel damage on camshaft
•Open or short circuit on CMP sensor
•Open or short circuit between CMP sensor and
PCM terminal 2J or 2M
Repair or replace malfunctioning parts.
If okay, go to next step.
No Inspect following:
•High-tension leads
•Ignition coil and connector
5 Install fuel pressure gauge between fuel pipe
and fuel distributor.
Start engine and run it at idle.
Measure fuel line pressure at idle.
Is fuel line pressure correct at idle?Yes Go to next step.
NoZero or low:
Inspect for clogged fuel line.
If okay, replace fuel pump unit
High:
Replace fuel pump unit.
6 Inspect for VTCS operation.
Does VTCS work properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
7Note
•The following test should be performed for
vehicles with variable valve timing control
system. Go to next step for vehicles
without variable valve timing control
system.
Inspect for variable valve timing control system
operation.
Does variable valve timing control system work
properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
8Note
•The following test should be performed for
vehicles with VIS. Go to next step for
vehicles without VIS.
Inspect for VIS operation.
Does VIS work properly?Yes Go to next step.
No Repair or replace malfunctioning parts.
9 Remove and shake PCV valve.
Does PCV valve rattle?Yes Go to next step.
No Replace PCV valve.
10 Inspect for restriction in the exhaust system.
Is there any restriction?Yes Inspect exhaust system.
No Go to next step.
11 Inspect for contaminated MAF sensor.
Is there any contamination?Yes Go to next step.
No Inspect for cause.
12 Inspect MAF sensor for contamination.
Is there any contamination?Yes Replace MAF sensor.
No Go to Step 14. (2WD)
Go to next step. (4WD)
13 Inspect electrically controlled 4WD system
operation.
Is operation of electrically controlled 4WD
system okay?Yes Go to next step.
No Repair or replace malfunctioning parts.
14 Is engine compression correct? Yes Inspect valve timing.
No Inspect for cause.
15 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM. STEP INSPECTION RESULTS ACTION

F1–64
TROUBLESHOOTING
NO.22 VIBRATION CONCERNS (ENGINE)A6E398018881204
Diagnostic procedure
End Of Sie
22 VIBRATION CONCERNS (ENGINE)
DESCRIPTION•Vibration from under hood or driveline
POSSIBLE CAUSE•Loose attaching bolts or worn parts
•Components malfunction such as worn parts
STEP INSPECTION RESULTS ACTION
1 Inspect following components for loose attaching
bolts or worn parts:
•Cooling fan
•Condenser fan
•Drive belt and pulleys
•Engine mounts
All items okay?Yes Inspect following systems:
•Wheels
•ATX
•Driveline
•Suspension
•Electrically controlled 4WD system
No Readjust or retighten engine mount installation
position.
Service if necessary for other parts.
2 Verify test results.
•If okay, return to diagnostic index to service any additional symptoms.
•If malfunction remains, replace PCM.