Mazda 6 2002, Workshop Manual

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F–122
ON-BOARD DIAGNOSTIC
5 VERIFY CURRENT INPUT SIGNAL STATUS
UNDER TROUBLE CONDITION
•
Inspect same PIDs as in Step 4 while
simulating FREEZE FRAME DATA condition.
•
Is there any signal which causes drastic
changes?
Yes Inspect suspected circuit and/or part according to
inspection results.
(See
F–45 PCM INSPECTION .)
Then go to Step 22.
No Go to next step.
6 INSPECT CMP SENSOR
•
Inspect CMP sensor.
(See
F–55 CAMSHAFT POSITION (CMP)
SENSOR INSPECTION .)
•
Is CMP sensor okay?
Yes Go to next step.
No Inspect installation condition and damages on timing belt
and gears, repair faulty parts.
•
If it is okay, replace CMP sensor.
Then go to Step 22.
7 VERIFY CKP SENSOR INSTALLATION
CONDITION
•
Inspect for CKP sensor looseness.
•
Is CKP sensor loosen?
Yes Retighten CKP sensor, then go to Step 22.
No Go to next step.
8 INSPECT IGNITION COIL OPERATION AND
HIGH-TENSION LEAD WITH TIMING LIGHT
•
Verify blinking condition on each cylinders
using timing light at idle.
•
Do all cylinders show blinking condition?
Yes Go to Step 12.
No Go to next step.
9 INSPECT HIGH-TENSION LEADS OF NO
BLINKING CYLINDER
•
Turn ignition key to OFF.
•
Inspect high-tension leads for improper
installation, corrosion on terminal, open lead
and damaged cover.
•
Is condition of high-tension lead okay?
Yes Go to next step.
No Replace faulty high-tension lead, then go to Step 22.
10 INSPECT POWER SUPPLY TERMINAL AT
IGNITION COIL CONNECTOR
•
Disconnect ignition coil connector.
•
Turn ignition key to ON (Engine OFF).
•
Measure voltage between ignition coil terminal
B (harness-side) and body ground.
•
Is there voltage reading B+ ?
Yes Go to next step.
No Inspect for open circuit between ignition coil connector and
ignition switch. Repair or replace wiring harness, then go to
Step 22.
11 INSPECT IGNITION COIL RESISTANCE
•
Inspect ignition coil resistance.
(See
G–9 IGNITION COIL INSPECTION .)
•
Is coil resistance okay?
Yes Go to step 22.
No Replace ignition coil, then go to Step 22.
12 INSPECT MAF PID
•
Start engine.
•
Access MAF PID using WDS or equivalent.
•
Verify that MAF PID changes quickly according
to race engine RPM.
•
Is MAF PID response okay?
Yes Go to next step.
No Replace MAF sensor, then go to Step 22.
13 INSPECT EXCESSIVE AIR SUCTION IN INTAKE
AIR SYSTEM
•
Inspect for air leakage at following:
— Between MAF sensor and throttle body
— Between throttle body and intake manifold
•
Is there any malfunction?
Yes Repair or replace suspected part, then go to Step 22.
No Go to next step.
14 INSPECT FUEL LINE PRESSURE
•
Inspect fuel line pressure.
(See
F–20 FUEL LINE PRESSURE
INSPECTION .)
•
Is fuel line pressure okay?
Yes Go to step 16.
No If fuel line pressure is too low, go to next step.
If fuel line pressure is excess high, replace fuel pump unit,
then go to Step 22.
STEP INSPECTION ACTION