P0374 Fault Code

Timing Reference High Resolution Signal A No Pulses

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0374 fault code indicates that the Engine Control Module (ECM) has detected an issue with the timing reference high-resolution signal A, specifically that no pulses are being received. This signal is crucial for the proper functioning of the ignition timing and fuel injection systems in modern vehicles.

What are the symptoms of the P0374 code?

When a vehicle has a P0374 fault code, you may experience:

• Engine misfiring or rough running during acceleration.
• Poor engine performance or stalling at idle.
• Illuminated check engine light on the dashboard.
• Difficulty starting the vehicle, especially after it has warmed up.

What causes the P0374 code?

Several factors can lead to a P0374 code, including:

• Faulty crankshaft or camshaft position sensors that fail to send signals.
• Wiring issues, such as frayed or corroded connections between sensors and the ECM.
• Issues with the timing belt or chain, leading to improper synchronization of engine components.
• A malfunctioning ECM itself, although this is less common.

How to fix P0374?

To address a P0374 code, you should follow these steps:

• Inspect and test the crankshaft and camshaft position sensors for proper functionality.
• Check wiring and connectors for any signs of damage or corrosion that could impede signal transmission.
• Verify that the timing belt or chain is properly aligned and functioning as intended.
• If no issues are found with the sensors or wiring, consider testing or replacing the ECM.