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Mazda 6. Manual - part 166

F–186

TROUBLESHOOTING

NO.1 MELTING OF MAIN OR OTHER FUSES

A6E398018881W03

End Of Sie

NO.2 MIL ILLUMINATES

A6E398018881W04

MELTING OF MAIN OR OTHER FUSES

[TROUBLESHOOTING HINTS]
Inspect condition of fuse.

Damaged fuse

Related wiring harness

MAIN

• IG KEY2 fuse

• AD FAN fuse

• FAN fuse

ENG +B

• PCM

IG KEY1

• Ignition switch

— ENGINE IG fuse
— METER IG fuse

IG KEY2

• Ignition switch

AD FAN

• Cooling fan relay

— Cooling fan motor

FAN

• Cooling fan relay (L8-DE, LF-DE (except G.C.C. specs.)

— Cooling fan motor

ENGINE IG

• Main relay

— PCM

• Ignition coil

• Condenser

METER IG

• Cooling fan relay

— PCM

ENG BAR

• VSS (ATX)

• OCV

• VIS solenoid valve

• VAD control solenoid valve

• Purge solenoid valve

• EGR valve

• MAF/IAT sensor

ENG BAR2

• Heated oxygen sensor heater

INJ

• PCM

• Fuel pump relay

— PCM

• Fuel injector

FUEL PUMP

• Fuel pump relay

— Fuel pump

MIL ILLUMITATES

DESCRIPTION

MIL is illuminated incorrectly.

POSSIBLE CAUSE

• PCM illuminates for emission-related concern (DTC is stored in PCM)

• Instrument cluster malfunction

Note

• If MIL blinks at steady rate, misfire condition could possibly exist.

TROUBLESHOOTING

F–187

Diagnostic procedure

End Of Sie

NO.3 WILL NOT CRANK

A6E398018881W05

Diagnostic procedure

STEP

INSPECTION

RESULTS

ACTION

Connect WDS or equivalent to DLC-2.
Retrieve any DTC.
Are there DTC displayed?

Yes

DTC is displayed:

• Go to appropriate DTC test.

No DTC is displayed:

• Inspect instrument cluster operation.

See Section T.

Verify test results.

• If okay, return to diagnostic index to service any additional symptoms.

• If malfunction remains, replace PCM.

WILL NOT CRANK

DESCRIPTION

Starter does not work.

POSSIBLE CAUSE

• Open starter circuit between ignition switch and starter

• TR switch malfunction (ATX)

• TR switch misadjustment (ATX)

• Low or dead battery.

• Charging system malfunction.

• Starter interlock switch malfunction (MTX with starter interlock system).

• Starter malfunction

• Seized/hydrolocked engine, flywheel or drive plate

• Immobilizer system (PATS) and/or circuit malfunction (if equipped).

STEP

INSPECTION

RESULTS

ACTION

Note

• The following test should be perform for

vehicles with immobilizer system. Go to
Step 10 for vehicles without immobilizer
system.

Connect WDS or equivalent to DLC-2.
Do following conditions appear?

• Engine is not completely started.

• DTC B1681 is displayed.

Yes

Both conditions appear:
Go to Step 4.

Either or other condition appears:
Go to next step.

Is coil connector securely connected to coil?

Yes

Go to next step.

Connect coil connector securely.
Return to Step 1.

Does security light illuminate?

Yes

Go to next step.

Inspect instrument cluster and wiring harness.

Connect WDS or equivalent to DLC-2 and
retrieve DTC.

DTC

B1213, B1342, B1600, B1601, B1602, B1681,

B2103, B2431

Yes

Go to appropriate DTC test.

Go to next step.

Is there continuity between PCM GND terminals
4X, 2AB, 2AC and GND?

Yes

Go to next step.

Repair or replace wiring harness.

Measure voltage between PCM GND terminals
4X, 2AB, 2AC and coil terminal C.
Is the voltage below 1.0?

Yes

Go to next step.

Repair or replace wiring harness.

Turn ignition switch ON position.
Access VPWR PID.
Is VPWR PID okay?

Specification

Battery voltage

Yes

Go to next step.

Repair or replace wiring harness.

Disconnect coil connector.
Turn ignition switch to ON position.
Is there battery voltage at coil connector terminal
D (harness-side)?

Yes

Inspect for following:

• Open or short circuit between coil terminal A and

PCM terminal 2Q.

• Open or short circuit between coil terminal B and

PCM terminal 2T.

Repair or replace wiring harness between coil
connector terminal D and fuse panel.

F–188

TROUBLESHOOTING

End Of Sie

Is there continuity between PCM terminal 4I and
starter relay with clutch pedal depressed (MTX
with starter interlock system), P or N position
(ATX)?

Yes

Go to next step.

Repair replace wiring harness.

Inspect following:

• Battery connection

• Battery condition

• Transaxle is in Park or Neutral. (ATX)

• Clutch is fully depressed. (MTX with starter

interlock system)

• Fuses

Are all items okay?

Yes

Go to next step.

Service as necessary.
Repeat Step 10.

Is clicking sound heard from starter when
ignition switch is turned to START?

Yes

Go to next step.

Go to Step 13.

Inspect starting system.
(See

G–12 STARTER INSPECTION

Is starting system okay?

Yes

Inspect for seized/hydrolocked engine, flywheel or
drive plate.
(See

H–15 FLYWHEEL INSPECTION

Repair or replace components as required.

Do any other electrical accessories work?

Yes

Go to next step.

Inspect charging system.
(See

G–4 BATTERY INSPECTION

(See

G–7 GENERATOR INSPECTION

Note

• Following test should be performed on

ATX only. For MTX, go to next step.

Connect WDS or equivalent to DLC-2.
Access TR PID.
Turn ignition switch to ON position.
Is TR PID indicated P/N when selecting P or N
position?

Yes

Go to next step.

Inspect adjustment of TR switch.
If TR switch is adjusted properly, inspect for open
circuit between TR switch and PCM terminal 1W or
starter.

Connect WDS or equivalent to DLC-2.
Retrieve any continuous memory DTCs.
Are there any continuous memory DTCs
displayed?

Yes

DTC is displayed:
Go to appropriate DTC test.
Communication error message is displayed:
Inspect for following:

• Open circuit between main relay and PCM terminal

2Y or 4V

• Open circuit between main relay terminal E and

PCM terminal 2X

• Main relay is stuck open.

• Open or poor GND circuit (PCM terminal 4X, 2AB

or 2AC)

• Poor connection of vehicle body GND

No DTC is displayed:
Inspect following:

• START circuit in ignition switch

• Open circuit between ignition switch and starter

• Starter interlock switch (MTX with stater interlock

system)

Retrieve any KOEO DTCs.
Are there DTCs displayed during KOEO
inspection?

Yes

DTC is displayed:
Go to appropriate DTC test.

No DTC is displayed:
Inspect following:

• START circuit in ignition switch

• Open circuit between ignition switch and starter

• Starter interlock switch (MTX with stater interlock

system)

Verify test results.

• If okay, return to diagnostic index to service any additional symptoms.

• If malfunction remains, replace PCM.

STEP

INSPECTION

RESULTS

ACTION

TROUBLESHOOTING

F–189

NO.4 HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK

A6E398018881W06

Diagnostic procedure

HARD TO START/LONG CRANK/ERRATIC START/ERRATIC CRANK

DESCRIPTION

• Starter cranks engine at normal speed but engine requires excessive cranking time before starting.

• Battery is in normal condition.

POSSIBLE CAUSE

• Spark leakage from high-tension leads

• Vacuum leakage

• Poor fuel quality

• Starting system malfunction

• Spark plug malfunction

• Air leakage from intake-air system

• Erratic signal from CKP sensor

• Erratic signal from CMP sensor

• Improper air/fuel mixture ratio control

• Air cleaner restriction

• IAC valve malfunction

• PCV valve malfunction

• Inadequate fuel pressure

• Purge solenoid valve malfunction

• MAF sensor contamination

• Restriction in exhaust system

• EGR valve malfunction

• Pressure regulator malfunction

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 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.
(See

F–17 BEFORE REPAIR PROCEDURE

(See

F–17 AFTER REPAIR PROCEDURE

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

Inspect for following:

• Vacuum leakage

• Proper fuel quality (e.g. proper octane,

contamination, winter/summer blend)

• Loose bands on intake-air system

• Cracks on intake-air system parts

• Air cleaner restriction

Are all items okay?

Yes

Go to next step.

Service as necessary.
Repeat Step 1.

Connect WDS or equivalent to DLC-2.
Retrieve any KOEO and KOER DTC.
Is any KOEO or KOER DTC displayed?

Yes

DTC is displayed:
Go to appropriate DTC test.

No DTC is displayed:
Go to next step.

Is engine overheating?

Yes

Go to symptom troubleshooting “No.17 Cooling system
concerns – Overheating”.

Go to next step.

Inspect for cracks on high-tension leads.
Are there any cracks on high-tension leads?

Yes

Repair suspected high-tension leads.

Go to next step.

Inspect spark plug conditions.
Is spark plug wet, covered with carbon or
grayish white?

Yes

Spark plug is wet or covered with carbon:
Inspect for fuel leakage from fuel injector.
Spark plug is grayish white:
Inspect for clogged fuel injector.

Install spark plugs on original cylinders.
Go to next step.

Content .. 164 165 166 167 ..