P0048 Mazda

DTC P0048 Variable boost control (VBC) solenoid valve control circuit high input
DETECTION CONDITION
•  The PCM monitors the VBC solenoid valve control signal. If the voltage at PCM terminal 104 remains high, the PCM determines that there is a VBC solenoid valve circuit problem.
POSSIBLE CAUSE
•  VBC solenoid valve malfunction
•  Connector or terminal malfunction
•  Short to power supply in the wiring harness between VBC solenoid valve terminal A and PCM terminal 104
•  PCM malfunction

 

STEP INSPECTION ACTION
1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has the FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR INFORMATION AVAILABILITY
•  Verify related service repair information availability.
•  Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
VERIFY CURRENT SIGNAL STATUS: IS CONCERN INTERMITTENT OR CONSTANT?
•  Connect the M-MDS to the DLC-2.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Run the vehicle under the FREEZE FRAME DATA stored condition.
•  Is the same DTC present?
Yes
Go to the next step.
No
Intermittent concern exists.
Perform the “INTERMITTENT CONCERNS TROUBLESHOOTING”.
4
CLASSIFY MALFUNCTION FOR INSPECT VBC SOLENOID VALVE CONTROL CIRCUIT OR OTHER
•  Turn the engine switch off.
•  Disconnect the VBC solenoid valve connector.
•  Turn the engine switch to the ON position (Engine off).
•  Measure the voltage between VBC solenoid valve terminal A (wiring harness-side) and body ground.
•  Is the voltage B+?
Yes
Go to the next step.
No
Go to Step 7.
5
INSPECT VBC SOLENOID VALVE CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY
•  Turn the engine switch off.
•  Disconnect the PCM connector and VBC solenoid valve connector.
•  Turn the engine switch to the ON position (Engine off).
•  Measure the voltage between PCM terminal 104 (wiring harness-side) and body ground.
•  Is the voltage B+?
Yes
Repair or replace the wiring harness for a short to power between VBC solenoid valve terminal A and PCM terminal 104, then go to Step 9.
No
Go to the next step.
6
INSPECT PCM CONNECTOR FOR POOR CONNECTION
•  Turn the engine switch off.
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 9.
No
Go to Step 9.
7
INSPECT VBC SOLENOID VALVE
•  Inspect the VBC solenoid valve.
•  Is there any malfunction?
Yes
Replace the VBC solenoid valve, then go to Step 9.
No
Go to the next step.
8
INSPECT VBC SOLENOID VALVE CONNECTOR FOR POOR CONNECTION
•  Turn the engine switch off.
•  Disconnect the VBC solenoid valve connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal, then go to the next step.
No
Go to the next step.
9
VERIFY THAT DTC P0048 TROUBLESHOOTING IS COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Run the vehicle under the FREEZE FRAME DATA stored condition.
•  Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
9
VERIFY AFTER REPAIR PROCEDURE
•  Perform the after repair procedure.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.