P0373 – OBD-II DTC

OBD-II DTC P0373 – Timing Reference High Resolution Signal A Too Few Pulses

DTC P0373 meaning

DTC P0373 refers to a diagnostic trouble code indicating that the engine control module (ECM) has detected a problem with the timing reference high-resolution signal A. Specifically, it means that there are too few pulses being received from the crankshaft or camshaft position sensors, which are crucial for proper engine timing and operation.

DTC P0373 symptoms

Common symptoms associated with DTC P0373 may include:

• Engine misfires
• Rough idling
• Difficulty starting the engine
• Loss of power during acceleration
• Check Engine Light (CEL) illuminated

DTC P0373 causes

Several factors can lead to the occurrence of DTC P0373, including:

• Faulty crankshaft or camshaft position sensors
• Wiring issues or damaged connectors in the sensor circuit
• Faulty engine control module (ECM)
• Timing belt or chain issues
• Mechanical problems within the engine affecting timing

DTC P0373 seriousness

DTC P0373 can be serious as it affects the engine’s timing, which is critical for optimal performance. If left unaddressed, it may lead to:

• Increased emissions
• Severe engine damage
• Reduced fuel efficiency
• Potential stalling or failure to start

How to diagnose DTC P0373

To diagnose DTC P0373, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the code.
2. Check for any additional trouble codes that may provide more context.
3. Inspect the crankshaft and camshaft position sensors for damage or wear.
4. Examine the wiring and connectors for any signs of corrosion or disconnection.
5. Test the sensors’ output using a multimeter to ensure they are functioning correctly.
6. Check the timing belt or chain for proper alignment and condition.
7. Perform a visual inspection of the engine for any mechanical issues.

How to fix DTC P0373 step-by-step instructions

To fix DTC P0373, follow these steps:

1. Address any wiring or connector issues found during diagnosis.
2. If the crankshaft or camshaft position sensors are faulty, replace them.
3. Repair or replace the timing belt or chain if it is misaligned or damaged.
4. Clear any debris or obstructions that may affect sensor operation.
5. Recheck the sensor outputs after repairs to ensure they are within specifications.
6. Clear the DTC using an OBD-II scanner and take the vehicle for a test drive.
7. Monitor for the reoccurrence of the code or any related symptoms.

How to erase DTC P0373

To erase DTC P0373, 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 Codes” 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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