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DTC P0091 [MZR-CD (RF Turbo)]

BME010200001W07

DTC P0091 | Suction control valve circuit low input
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DETECTION CONDITION | • PCM monitors input voltage from suction control valve while engine is running. If input voltage from suction control valve does not change from off to on, PCM determines suction control valve circuit low input.
POSSIBLE CAUSE | • Suction control valve malfunction • Connector or terminal malfunction • Short to GND in wiring between suction control valve terminal A and PCM terminal 93 • Short to GND in wiring between suction control valve terminal B and PCM terminal 94 • Open circuit in wiring between suction control valve terminal A and PCM terminal 93
• Open circuit in wiring between suction control valve terminal B and PCM terminal 94
• PCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Check for related Service Information availability. • Is any related repair information available? | Yes | Perform repair or diagnosis according to available Service Information. • If vehicle is not repaired, go to next step.
No | Go to next step.
2 | INSPECT POOR CONNECTION OF SUCTION CONTROL VALVE CONNECTOR • Turn engine switch to OFF. • Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.). • Is there any malfunction? | Yes | Repair or replace suspected terminal, go to Step 7.
No | Go to next step.
3 | INSPECT SUCTION CONTROL VALVE CIRCUIT FOR SHORT TO GND • Turn engine switch to OFF. • Inspect continuity between following harnesses:

  - Suction control valve terminal A and body GND.
  - Suction control valve terminal B and body GND.

• Is there continuity?
Yes
Repair or replace harness for short to GND, go to Step 7.
No | Go to next step.
4 | INSPECT SUCTION CONTROL VALVE • Inspect suction control valve. (See SUCTION CONTROL VALVE INSPECTION [MZR-CD (RF Turbo)].) • Is there any malfunction? | Yes | Repair supply pump, go to Step 7. (See SUPPLY PUMP INSPECTION [MZR-CD (RF Turbo)].)
No | Go to next step.
5 | INSPECT POOR CONNECTION OF PCM CONNECTOR • Turn engine switch to OFF. • Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc.). • Is there any malfunction? | Yes | Repair or replace suspected terminal, go to Step 7.
No | Go to next step.
6 | INSPECT SUCTION CONTROL VALVE CIRCUIT FOR OPEN • Turn engine switch to OFF. • Inspect continuity between following harnesses:

  - Suction control valve terminal A and PCM terminal 93.
  - Suction control valve terminal B and PCM terminal 94.

• Is there continuity?
Yes
Go to next step.
No | Repair or replace harness for open, go to next step.
7 | VERIFY TROUBLESHOOTING OF DTC P0091 COMPLETED • Make sure to reconnect all disconnected connectors. • Clear DTC from PCM memory using WDS or equivalent. • Start engine. • Is same DTC present? | Yes | Replace PCM, go to next step. (See PCM REMOVAL/INSTALLATION [MZR-CD (RF Turbo)].)
No | Go to next step.
8 | VERIFY AFTER REPAIR PROCEDURE • Perform "After Repair Procedure". (See AFTER REPAIR PROCEDURE [MZR-CD (RF Turbo)].) • Is there any DTC present? | Yes | Go to applicable DTC inspection. (See DTC TABLE [MZR-CD (RF Turbo)].)
No | Troubleshooting completed.