LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2011 >> RX-8 R3, 1.3 4 >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P0523
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0523

DTC P0523 Oil pressure sensor circuit high input
DETECTION CONDITION 
  • The voltage of oil pressure sensor input terminal is more than 4.8 V for 0.5 s or more. 

Diagnostic support note 
  • This is a continuous monitor (other).
  • The MIL does not illuminate.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is not available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • Oil pressure sensor connector or terminals malfunction
  • PCM connector or terminals malfunction
  • Short to power supply in wiring harness between oil pressure sensor terminal B and PCM terminal 2R
  • Open circuit in wiring harness between oil pressure sensor terminal A and PCM terminal 2M
  • Oil pressure sensor malfunction
  • PCM malfunction
G07878125
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line 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.
2 INSPECT OIL PRESSURE SENSOR CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the oil pressure sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 7.
No Go to the next step.
3 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition 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 connector and/or terminals, then go to Step 7.
No Go to the next step.
4 INSPECT OIL PRESSURE SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Oil pressure sensor and PCM connectors are disconnected.
  • Turn the ignition switch to the ON position (engine off).
  • Measure the voltage between oil pressure sensor terminal B (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 7.
No Go to the next step.
5 INSPECT OIL PRESSURE SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT 
  • Oil pressure sensor and PCM connectors are disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between oil pressure sensor terminal A (wiring harness-side) and PCM terminal 2M (wiring harness-side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 7.
6 INSPECT OIL PRESSURE SENSOR 
 Yes Replace the oil pressure sensor, then go to the next step.
(See OIL PRESSURE SENSOR REMOVAL/INSTALLATION ).
No Go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P0523 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the KOER self test (See KOEO/KOER SELF TEST ).
  • Is the same DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
8 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
scientia non olet · About LEMON Manuals