Dtc P0191 - Mazda Mazda6 Workshop Manual Supplement

DTC P0191

DTC P0191 Fuel pressure sensor circuit performance problem
• PCM monitors fuel pressure in common rail from fuel pressure sensor while engine is running. PCM
DETECTION
calculates difference between actual fuel pressure and target fuel pressure. If pressure difference exceeds
CONDITION
preprogrammed criteria, PCM determines fuel pressure sensor circuit performance problem.
• Fuel pressure sensor malfunction
• Suction control valve malfunction
POSSIBLE
• Clogged fuel line
CAUSE
• PCM malfunction
Diagnostic procedure
STEP
1 VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Check for related Service Information
availability.
• Is any related repair information available?
2 FOLLOW OTHER DETECTED DTC FIRST
• Turn engine switch to OFF.
• Start engine.
• Have P0091, P0092, P0192, P0193 been
detected?
3 INSPECT FUEL PRESSURE SENSOR
• Inspect fuel pressure sensor.
(See F2–79 FUEL PRESSURE SENSOR
INSPECTION)
• Is there any malfunction?
4 INSPECT SUCTION CONTROL VALVE
• Inspect suction control valve.
(See F2–54 SUCTION CONTROL VALVE
INSPECTION)
• Is there any malfunction?
5 INSPECT FUEL LINE
• Turn engine switch to OFF.
• Inspect for clogs in following fuel lines for each
cylinder:
— Common rail and fuel injector.
— Common rail and fuel tank.
•
Is there any malfunction?
6 VERIFY TROUBLESHOOTING OF DTC P0016
COMPLETED
• Make sure to reconnect all disconnected
connectors.
• Clear DTC from PCM memory using WDS or
equivalent.
• Start engine.
• Is same DTC present?
7 VERIFY AFTER REPAIR PROCEDURE
• Perform "After Repair Procedure".
(See F2–86 AFTER REPAIR
• Is there any DTC present?
End Of Sie
F2–124
ON-BOARD DIAGNOSTIC
INSPECTION
PROCEDURE)
Yes Perform repair or diagnosis according to available Service
Information.
• If vehicle is not repaired, go to next step.
No Go to next step.
Yes Go to applicable DTC inspection.
(See F2–87 DTC TABLE)
No Go to next step.
Yes Replace common rail, go to Step 6.
(See F2–53 SUPPLY PUMP
No Go to next step.
Yes Repair supply pump, go to Step 6.
(See F2–54 SUPPLY PUMP
No Go to next step.
Yes Repair or replace suspected fuel line, go to next step.
No Go to next step.
Yes Replace PCM, go to next step.
(See F2–64 PCM REMOVAL/INSTALLATION)
No Go to next step.
Yes Go to applicable DTC inspection.
(See F2–87 DTC TABLE)
No Troubleshooting completed.
A6E407001082221
ACTION
REMOVAL/INSTALLATION)
INSPECTION)