C1117 – OBD-II DTC

OBD-II DTC C1117 – RPM Input Circuit Failure

DTC C1117 meaning

DTC C1117 refers to a diagnostic trouble code indicating an issue with the RPM input circuit. This code is triggered when the Engine Control Module (ECM) detects a malfunction in the signal from the RPM sensor, which is crucial for engine performance and operation. The RPM input circuit is responsible for relaying engine speed information to the ECM, which uses this data to manage various engine functions.

DTC C1117 symptoms

Common symptoms associated with DTC C1117 may include:

• Engine stalling or misfiring
• Unusual engine behavior or performance issues
• Illumination of the check engine light
• Difficulty in starting the engine
• Erratic or fluctuating RPM readings on the dashboard

DTC C1117 causes

Several factors can lead to the triggering of DTC C1117, including:

• Faulty RPM sensor
• Damaged or corroded wiring in the RPM input circuit
• Loose or poor electrical connections
• Issues with the Engine Control Module (ECM)
• Mechanical problems affecting the engine’s ability to produce RPM signals

DTC C1117 seriousness

DTC C1117 is considered a serious issue as it can affect engine performance and drivability. If left unaddressed, it may lead to further complications, including:

• Increased emissions
• Potential engine damage
• Reduced fuel efficiency
• Safety risks due to engine stalling

How to diagnose DTC C1117

To diagnose DTC C1117, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the C1117 code.
2. Inspect the RPM sensor and its wiring for any visible damage or corrosion.
3. Check electrical connections for looseness or poor contact.
4. Test the RPM sensor’s output using a multimeter to ensure it is functioning correctly.
5. Examine the ECM for any faults or software issues.
6. Clear the code and perform a road test to see if the code reappears.

How to fix DTC C1117 step-by-step instructions

To fix DTC C1117, follow these steps:

1. Inspect and replace the RPM sensor if it is found to be faulty.
2. Repair or replace any damaged wiring in the RPM input circuit.
3. Ensure all electrical connections are clean, tight, and free of corrosion.
4. If necessary, reprogram or replace the ECM.
5. After repairs, clear the DTC using an OBD-II scanner.
6. Conduct a road test to verify that the issue has been resolved and the code does not return.

How to erase DTC C1117

To erase DTC C1117, 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 reappear.

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