OBD-II Code P0347 — What It Means & How to Fix It

What Does This Error Mean?

P0347 means the camshaft position sensor circuit on Bank 1 is reading a voltage that is too low. Bank 1 is the side of the engine that contains cylinder 1. A low voltage on the cam sensor circuit usually means the sensor isn't getting proper power, has a wiring problem, or has failed internally. The ECM can't accurately time the engine without this data, which can cause rough running, hard starting, or stalling. This is a critical sensor and should be addressed promptly.

Affected Models

All vehicles 1996+
Common in Ford and Lincoln vehicles
Common in GM vehicles with V6 and V8 engines
Common in Honda and Acura vehicles
Common in Dodge, Chrysler, and Jeep vehicles

Common Causes

Open or broken wire in the cam sensor circuit — the signal wire has lost continuity
Failed camshaft position sensor with an open internal coil producing no output
Missing or low reference voltage supply to the sensor — a broken 5V supply wire from the ECM
Poor ground connection at the sensor or at the ECM cam sensor circuit
Corroded or disconnected connector at the camshaft position sensor

How to Fix It

Scan for all codes and check for P0340 (circuit malfunction) or P0342 (circuit low) alongside P0347. Multiple related codes confirm there is a significant problem with the cam sensor circuit on Bank 1 rather than a simple transient fault.

Also check for any correlation codes (P0016, P0017) which would indicate a mechanical cam/crank timing issue rather than just a sensor or circuit fault.
Locate the Bank 1 camshaft position sensor and unplug the connector. Inspect it for corrosion, moisture, or pushed-back pins. Clean with electrical contact cleaner and reconnect firmly. A dirty or loose connector is a common cause of low signal codes.

On many V6 engines, the Bank 1 cam sensor is on the driver's side cylinder head.
Test the 5V reference supply to the sensor. With the connector unplugged and the ignition ON (not started), measure the voltage on the 5V reference wire from the ECM. If there is no voltage or significantly less than 5V, there is an open or damaged wire between the ECM and the sensor.

A missing reference voltage means the sensor has nothing to work with and will produce no output.
Test the sensor ground wire. Measure resistance between the ground pin on the sensor connector and a clean chassis ground point. It should read near 0 ohms. High resistance on the ground circuit causes the entire sensor circuit to operate at reduced voltage.

Cam sensor ground issues are less common but are sometimes caused by a loose engine ground strap.
If power and ground supply are correct, replace the camshaft position sensor. An open internal coil will cause the sensor to produce no output, which the ECM reads as a low voltage condition. Clear the code after replacement and verify with a full drive cycle.

When replacing the sensor, also replace the connector pigtail if there is any sign of corrosion — a corroded connector will re-contaminate a new sensor over time.

When to Call a Professional

If the connector and visible wiring appear intact but P0347 persists, have a mechanic test the 5V reference and ground supply to the sensor. A missing 5V reference means a broken wire between the ECM and the sensor. That kind of wiring fault is best traced with a wiring diagram. Expect $100-$200 for diagnosis and $100-$250 for sensor replacement with labor.

Frequently Asked Questions

What is the difference between P0347 and P0342?

Both are low voltage codes for the Bank 1 camshaft position sensor, but they come from different sensor positions. In the OBD-II code structure, P0340 through P0344 relate to 'Camshaft Position Sensor A' (typically intake cam, Bank 1). P0345 through P0349 relate to 'Camshaft Position Sensor A' on Bank 2, or alternate cam sensor positions. The exact meaning varies slightly by manufacturer — check your vehicle's service manual for the precise sensor assignment.

Can I drive with P0347?

For a short distance — yes. But the engine will not be operating at its best without a reliable cam position signal. On variable valve timing engines, the VVT system may also be disabled while the fault is active, further reducing performance. Avoid long highway trips until the fault is repaired.

Is P0347 an expensive repair?

Usually not. The cam sensor itself costs $20-$80 for a quality part. Labor is typically 30-60 minutes if the sensor is accessible. The main cost variable is if the problem turns out to be wiring — tracing an open circuit can add 1-2 hours of diagnostic time. Total repair cost is usually $100-$250.