Timing Reference High Resolution Signal B No Pulses
Your engine's computer isn't receiving timing signals from a sensor that helps it know exactly when to fire the spark plugs. It's like a drummer not hearing the beat from the conductor.
The ECM monitors the crankshaft position sensor B (CMP Bank 2) for high-resolution timing pulses needed for precise ignition control. When no pulses are detected within the expected window, the ECU cannot determine engine position and triggers the fault. The sensor typically generates voltage transitions at each cam lobe passage.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Sensor pulse frequency | Continuous pulses during cranking/running | Zero or missing pulses for more than 1 revolution |
| Signal voltage transitions | 0.5-4.5V oscillation pattern | Flat or no voltage change detected |
Code P0380 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0380 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.