The P0337: Crankshaft Position Sensor A Circuit Low Input code indicates that the engine control module (ECM) has detected a low input signal from the crankshaft position sensor A. This sensor monitors the position and rotational speed of the crankshaft, and the ECM uses this information to adjust engine timing and fuel injection. A low signal from the sensor can be caused by a faulty sensor, wiring issues, or other circuit problems.
P0337 – Quick Overview
| Meaning | P0337: Crankshaft Position Sensor A Circuit Low Input |
| Is it serious? | Yes, this code is serious as it can lead to improper engine timing, causing poor performance, misfires, or stalling. |
| Possible causes | – Faulty crankshaft position sensor – Low input signal – Wiring issues |
| How to diagnose? | – Test sensor input – Inspect and repair wiring – Replace sensor if necessary |
P0337 Meaning
The P0337: Crankshaft Position Sensor A Circuit Low Input code means that the ECM is receiving a lower-than-expected signal from crankshaft position sensor A. The sensor provides critical data about the crankshaft’s position and speed, which the ECM uses to manage engine timing. A low input signal could lead to issues such as engine misfires, poor acceleration, or even stalling, and can result from a failing sensor, signal interruptions, or wiring faults.
Step-by-step diagnostic guide
Follow these steps to diagnose and resolve the P0337 code by addressing potential causes one by one.
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for additional related codes that may provide more insight into the issue. | OBD-II Scanner |
| Inspect Crankshaft Position Sensor A | Visually inspect the sensor for signs of damage, wear, or corrosion. Ensure that the sensor is properly mounted and connected securely. | Flashlight, Safety Gloves |
| Test Crankshaft Position Sensor Input | Use a multimeter to measure the signal from the crankshaft position sensor. Compare the readings to the manufacturer’s specifications to determine if the sensor is functioning properly. | Multimeter, Manufacturer’s Specifications |
| Inspect and Repair Wiring | Check the wiring and connections related to the sensor for signs of wear, loose connections, or corrosion. Repair or replace damaged wiring as necessary. | Flashlight, Wiring Repair Kit |
| Replace the Sensor if Necessary | If the sensor is faulty or not providing the correct signal, replace it with a new sensor to ensure accurate crankshaft position readings. | Replacement Crankshaft Position Sensor, Safety Gloves |
| Clear the Code and Test Drive | After completing repairs, clear the P0337 code using an OBD-II scanner. Test drive the vehicle to ensure the problem is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | After the test drive, re-scan the vehicle to confirm that the P0337 code has not returned. If the code reappears, further diagnosis may be necessary. | OBD-II Scanner |
This diagnostic guide will help you accurately identify and resolve the P0337 code, ensuring that the crankshaft position sensor A is functioning correctly and providing proper input signals to the ECM to maintain optimal engine timing and performance.
Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)