Mazda 6 2002, Руководство по ремонту

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ON-BOARD DIAGNOSTIC
F–73
F
DTC P0012
A6E397001084W03
Diagnostic procedure
DTC P0012 CMP - Timing over-retarded
DETECTION
CONDITION
•
Actual valve timing is over-retarded by 5 deg. from target valve timing for 5 s when the OCV system control
is within feed-back range.
Diagnostic support note
•
This is a continuous monitor (CCM).
•
MIL illuminates if PCM detects the above malfunction condition during first drive cycles.
•
PENDING CODE is available if PCM detects the above malfunction condition.
•
FREEZE FRAME DATA is available.
•
DTC is stored in PCM memory.
POSSIBLE
CAUSE
•
OCV (oil control valve) malfunction
•
Low engine oil pressure
•
Spool valve in OCV (oil control valve) is stuck in retard position.
•
Vriable valve timing actuator is stuck in retard position.
•
Following oil runners are clogged or have leakage.
Oil runners
•
Between oil pressure switch and OCV (oil control valve)
•
Between OCV (oil control valve) and variable valve timing actuator
•
In variable valve timing actuator
•
Loose timing belt or improper valve timing due to timing belt slippage
•
PCM malfunction
STEP INSPECTION ACTION
1 PERFORM DTC CONFIRMATION PROCEDURE
•
Perform DTC CONFIRMATION PROCEDURE.
(See
F–66 DTC CONFIRMATION
PROCEDURE .)
•
Is same DTC present?
Yes Go to next step.
No Intermittent concern exists. Go to INTERMITTENT
CONCERN TROUBLESHOOTING procedure.
(See
F–227 INTERMITTENT CONCERN
TROUBLESHOOTING .)
2 VERIFY RELATED PENDING CODE OR
STORED DTCS
•
Is DTC P0010 present?
Yes Go to DTC P0010 troubleshooting procedure.
(See F–70 DTC P0010 )
No Go to next step.
3 VERIFY ENGINE OIL PRESSURE
•
Start engine.
•
Does oil pressure warning light illuminate?
Yes Inspect engine oil pressure.
(See D–3 OIL PRESSURE INSPECTION )
No Go to next step.
4 VERIFY TIMING BELT INSTALLATION
•
Stop engine.
•
Remove timing belt cover.
•
Is camshaft timing mark at correct point?
(See
B–10 TIMING CHAIN REMOVAL/
INSTALLATION .)
Yes Go to next step.
No Reinstall timing belt, then go to Step 7.
5 INSPECT OCV FOR MALFUNCTION
•
Stop engine.
•
Remove OCV.
•
Inspect position of spool valve in OCV.
•
Is spool valve located at valve retard position?
Yes VARIABLE VALVE TIMING MECHANISM IS NORMAL
Note
•
This DTC detected by intermittent concern.
•
Intermittent concern might be removed by cleaning
mode of variable valve timing control function.
Go to next step.
No Replace OCV, then go to Step 7.
6 INSPECT ENGINE OIL RUNNER
•
Inspect following engine oil runners for
clogging or leakage.
— Beetween oil pressure switch and OCV
— Between OCV and variable valve timing
actuator
— In variable valve timing actuator
•
Is there any clogging or leakage?
Yes Repair or replace suspected runner, then go to next step.
No VARIABLE VALVE TIMING MECHANISM IS NORMAL
Note
•
This DTC is detected by intermittent concern.
•
Intermittent concern might be removed by cleaning
mode of variable valve timing control function.
Go to next step.