P0393
UniversalCamshaft Position Sensor B Circuit High Input (Bank 2)
Medium SeverityThis code indicates that the Engine Control Module (ECM) has detected a voltage signal from the camshaft position sensor B on engine Bank 2 that is higher than its expected operating range. This typically points to an electrical issue with the sensor itself, its wiring, or connector, which can severely impact the engine's ability to synchronize ignition and fuel injection.
⚠️ Before You Begin (Safety First)
Always disconnect the battery before performing any electrical work or replacing sensors to prevent accidental shorts or injury. Allow the engine to cool down completely before working near hot components to avoid burns. Wear appropriate safety gear, such as gloves and eye protection, when working on your vehicle.
Common Symptoms
- Check Engine Light illuminated
- Engine cranks but won't start
- Rough idling
- Engine stalling
- Reduced engine power or hesitation
- Poor fuel economy
- Engine entering 'limp mode'
Common Causes
- Faulty Camshaft Position Sensor B (Bank 2)
- Damaged, frayed, or corroded wiring in the sensor circuit
- Corroded or loose sensor connector
- Short circuit to voltage in the sensor's signal or reference circuit
- Problem with the Engine Control Module (ECM) (less common)
Frequently reported on: 2007-2015 Honda Pilot (V6), 2008-2016 Toyota Highlander (V6), 2009-2017 Chevrolet Silverado 1500 (V8), 2006-2013 Nissan Murano (V6), 2005-2010 Ford Explorer (V6/V8)
Diagnostic Steps
- Retrieve and record all stored DTCs and freeze frame data using an OBD-II scan tool.
- Visually inspect the Camshaft Position Sensor B (Bank 2) and its electrical connector and wiring for any signs of damage, corrosion, or loose connections.
- Clear the code and perform a test drive under varying conditions to see if the code returns.
- Using a multimeter, test the sensor's voltage output and resistance according to your vehicle's service manual specifications.
- If the sensor tests faulty, replace the Camshaft Position Sensor B (Bank 2). Ensure the new sensor is correctly installed and the connector is secure.
- After replacement, clear the DTCs and test drive the vehicle again to confirm the repair.
👨🔧 When to Call a Professional
If replacing the camshaft position sensor B does not resolve the issue, or if diagnostic steps indicate a complex wiring harness problem or an intermittent short circuit, it is strongly recommended to consult a professional technician. Advanced diagnostic tools and expertise are often required for pinpointing such electrical faults accurately.
Commonly Asked Questions
What does 'Bank 2' refer to?
Bank 2 refers to the cylinder bank that does not contain cylinder number one. In V-type engines, there are two banks, and this code specifically points to an issue on the 'other' bank.
Can I drive my car with a P0393 code?
It is not recommended to drive for an extended period with a P0393 code. While you might be able to, it can lead to engine performance issues, potential stalling, reduced power, or prevent the engine from starting, increasing the risk of further damage.
Is this code always caused by a bad sensor?
Not necessarily. While a faulty sensor is a common cause, the 'circuit high input' can also be due to damaged wiring (e.g., a short to voltage), a corroded connector, or even an issue with the Engine Control Module (ECM), although ECM problems are less frequent.
What tools do I need to diagnose P0393?
You will typically need an OBD-II scan tool to read and clear codes, basic hand tools (wrenches, sockets), and a multimeter to test the sensor's voltage and resistance, and to check for continuity and shorts in the wiring.
How do I find the Camshaft Position Sensor B on Bank 2?
The exact location varies significantly by vehicle make and model. You should consult your vehicle's specific service manual or an online repair guide for precise diagrams and instructions on locating Camshaft Position Sensor B on Bank 2 for your engine configuration.