Mazda 6 2002 - Dtc P0012

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.