P1691 – OBD-II DTC

OBD-II DTC P1691 – Metering Oil Pump Stepping Motor Circuit Malfunction

DTC P1691 meaning

DTC P1691 refers to a malfunction in the metering oil pump stepping motor circuit. This code indicates that the Engine Control Module (ECM) has detected an issue with the electrical circuit that controls the stepping motor responsible for regulating the oil pump’s operation. The metering oil pump is crucial for ensuring proper lubrication and performance of the engine, and any malfunction can lead to significant engine issues.

DTC P1691 symptoms

Common symptoms associated with DTC P1691 may include:

• Illuminated check engine light
• Engine performance issues, such as stalling or rough idling
• Decreased fuel efficiency
• Unusual engine noises
• Increased engine temperature

DTC P1691 causes

Several factors can lead to the triggering of DTC P1691, including:

• Faulty metering oil pump stepping motor
• Wiring issues, such as shorts or open circuits in the motor circuit
• Corroded or loose electrical connectors
• Faulty Engine Control Module (ECM)
• Oil pump malfunction

DTC P1691 seriousness

DTC P1691 is considered a serious issue as it can affect engine lubrication and performance. If left unaddressed, it may lead to severe engine damage, increased wear, and potential engine failure. It is crucial to diagnose and repair this issue promptly to maintain the vehicle’s reliability and longevity.

How to diagnose DTC P1691

To diagnose DTC P1691, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P1691 code.
2. Inspect the wiring and connectors related to the metering oil pump stepping motor for any visible damage or corrosion.
3. Test the resistance of the stepping motor using a multimeter to ensure it is within specifications.
4. Check for any additional trouble codes that may provide further insight into the issue.
5. Perform a visual inspection of the oil pump and its operation.

How to fix DTC P1691 step-by-step instructions

To fix DTC P1691, follow these step-by-step instructions:

1. Disconnect the battery to ensure safety while working on the electrical system.
2. Inspect and repair any damaged wiring or connectors related to the metering oil pump stepping motor.
3. If the stepping motor is faulty, replace it with a new one.
4. Reconnect the battery and clear the DTC using an OBD-II scanner.
5. Start the engine and monitor for any reoccurrence of the P1691 code.

How to erase DTC P1691

To erase DTC P1691, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the engine to ensure the code does not return.

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