P0372
UniversalTiming Reference High Resolution Signal A Too Few Pulses indicates that the powertrain control module (PCM) has detected an insufficient number of pulses from the crankshaft position sensor or camshaft position sensor "A" circuit, which is used for engine timing reference.
High SeverityThe engine's computer isn't getting enough critical timing signals from a sensor, often the crankshaft position sensor or camshaft position sensor. This can cause the engine to run poorly, stall unexpectedly, or prevent it from starting at all.
⚠️ Before You Begin (Safety First)
Always ensure the engine is cool before working on it. Disconnect the battery's negative terminal before performing any electrical work to prevent accidental short circuits or injury. Be cautious of hot engine components and rotating parts if the engine is running. Wear appropriate personal protective equipment.
Common Symptoms
- Check Engine Light illuminated
- Engine cranks but does not start
- Engine stalls unexpectedly
- Rough idling or misfires
- Reduced engine performance or acceleration
Common Causes
- Faulty Crankshaft Position Sensor
- Faulty Camshaft Position Sensor
- Damaged or corroded wiring/connector for the sensor circuit
- Damaged reluctor wheel or tone ring
- Poor electrical connection
- PCM failure (rare)
Frequently reported on: General/Universal
Diagnostic Steps
- Inspect the wiring harness and connector for the crankshaft position sensor and camshaft position sensor for any visible damage, corrosion, or loose connections.
- Check the sensor's mounting for looseness or damage.
- If accessible and comfortable, use a multimeter to test the sensor's resistance (refer to service manual specifications).
- Consider replacing the suspected sensor (crankshaft position sensor or camshaft position sensor) if no other issues are found and symptoms persist.
👨🔧 When to Call a Professional
If the engine is repeatedly stalling or will not start, or if diagnostic steps do not resolve the issue, it is highly recommended to consult a professional mechanic for advanced diagnostics. Complex electrical testing may be required.
Commonly Asked Questions
What does "Timing Reference High Resolution Signal A Too Few Pulses" mean?
It means the engine's computer isn't receiving enough precise signals from a critical engine sensor, typically the crankshaft position sensor or camshaft position sensor, which it uses to determine engine speed and position for proper ignition and fuel injection timing.
Can I drive with a P0372 code?
It is generally not recommended to drive with this code. It can lead to sudden engine stalling, difficulty starting, or complete engine failure, which can be dangerous.
What is the difference between a crankshaft and camshaft position sensor?
The crankshaft position sensor monitors the position and speed of the crankshaft, which is crucial for engine timing. The camshaft position sensor monitors the position of the camshafts to synchronize fuel injection and ignition with valve timing. Both are vital for engine operation.
Is this an expensive repair?
The cost varies significantly. The sensor itself might be moderately priced, but labor costs can increase if the sensor is difficult to access. If the issue is wiring, it might be a simpler fix.
How can I tell if it's the crankshaft or camshaft sensor?
A professional scan tool can often provide more specific data, indicating which sensor is reporting the issue. Sometimes the vehicle's symptoms (e.g., cranking without starting often points more to a crankshaft sensor) can also give clues. Visual inspection of both sensor's wiring is a good starting point.