P0728 – OBD-II DTC

OBD-II DTC P0728 – Engine Speed Input Circuit No Signal

DTC P0728 meaning

DTC P0728 indicates that the Engine Control Module (ECM) has detected a problem with the engine speed input circuit. Specifically, it means that the ECM is not receiving a signal from the engine speed sensor, which is crucial for proper engine operation and transmission control.

DTC P0728 symptoms

Common symptoms associated with DTC P0728 may include:

• Illuminated check engine light
• Rough engine idle
• Transmission shifting issues
• Decreased fuel efficiency
• Loss of power during acceleration

DTC P0728 causes

Several factors can lead to the occurrence of DTC P0728, including:

• Faulty engine speed sensor
• Wiring issues or damaged connectors in the engine speed input circuit
• Faulty ECM
• Corrosion or poor connections in the sensor circuit
• Mechanical issues affecting the engine or transmission

DTC P0728 seriousness

DTC P0728 is considered a moderate to serious issue. If left unaddressed, it can lead to:

• Increased wear and tear on the engine and transmission
• Potential for further damage to the vehicle’s drivetrain
• Unsafe driving conditions due to erratic shifting or loss of power

How to diagnose DTC P0728

To diagnose DTC P0728, follow these steps:

1. Use an OBD-II scanner to confirm the DTC and check for any related codes.
2. Inspect the engine speed sensor and its wiring for damage or disconnection.
3. Test the engine speed sensor’s output using a multimeter.
4. Check the ECM for proper operation and any software updates.
5. Examine the vehicle’s ground connections and power supply to the sensor.

How to fix DTC P0728 step-by-step instructions

To fix DTC P0728, follow these steps:

1. Repair or replace any damaged wiring or connectors in the engine speed input circuit.
2. If the engine speed sensor is faulty, replace it with a new one.
3. Ensure all connections are clean and secure, eliminating any corrosion.
4. Recheck the ECM for any updates or faults and replace if necessary.
5. Clear the DTC using an OBD-II scanner and test drive the vehicle to ensure the issue is resolved.

How to erase DTC P0728

To erase DTC P0728, 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 codes.
5. Disconnect the scanner and start the engine to verify that the code does not reappear.

Recommended tools for OBD-II diagnostics

Explore our expert picks: The Best OBD2 Scanners for 2025

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.