P0397
Fix within a few daysThe engine computer is receiving a lower-than-expected electrical signal from the camshaft position sensor on Bank 2.
Code P0397 means the engine computer detects a low signal from the Bank 2 camshaft position sensor. Common causes: faulty sensor (60%), wiring issues (30%). Drivability: Limit driving, fix within a few days. Repair cost: $70-$250 DIY, $150-$500 professional.
Can I Drive With P0397?
Limit driving, fix within a few days
Essential trips under 10 miles, avoid highways and heavy acceleration.
Stop driving immediately if: Engine stalls repeatedly, won't start, or you experience significant power loss.
Symptoms of P0397
- 1Check Engine Light is on
- 2Engine is hard to start or won't start
- 3Engine stalls unexpectedly
- 4Engine runs rough or idles poorly
- 5Reduced engine power or acceleration
- 6Poor fuel economy
Common Causes of P0397
Parts most likely causing this code, ranked by probability
The sensor itself is faulty and sending a weak or incorrect signal to the engine computer.
60% of P0397 cases are fixed by replacing this part
Damaged, corroded, or loose wires/connectors prevent the sensor's signal from reaching the engine computer correctly.
30% of P0397 cases are fixed by repairing wiring or connectors
An internal ECM fault can misinterpret or fail to receive the camshaft position sensor signal.
5% of P0397 cases are fixed by replacing or reprogramming the ECM
Incorrect engine timing can cause the camshaft position sensor to report out-of-range values, which the ECM might interpret as a circuit issue.
5% of P0397 cases are related to underlying timing component problems
Check These First (Before Buying Parts)
- Visually inspect the Bank 2 camshaft position sensor and its electrical connector for any visible damage, corrosion, or loose connections.
- Ensure the battery voltage is good; a weak battery can sometimes cause low voltage codes.
- Clear the code with a scan tool and see if it immediately returns.
How to Diagnose P0397
- 1Visually inspect the camshaft position sensor (Bank 2) and its wiring harness for any obvious damage, fraying, or corrosion.
- 2Check the electrical connector at the sensor for looseness, bent pins, or corrosion. Disconnect and reconnect it to ensure a solid connection.
- 3Use a multimeter to test the voltage at the sensor connector and the resistance of the sensor itself (refer to service manual specifications).
- 4Use a scan tool to monitor live data from the camshaft position sensor while cranking or running the engine (if possible). Look for erratic readings or no signal.
- 5Perform a continuity test on the wiring between the camshaft position sensor connector and the engine control module (ECM) connector.
- 6If all sensor and wiring tests pass, consider testing the ECM, though this is a rare cause.
P0397 on Popular Vehicles
Honda Accord
2003-2024P0397 on these models can sometimes be linked to issues with the VTEC system, specifically the VTEC oil pressure switch or solenoid wiring, which can affect camshaft signal integrity.
55% fixed by replacing the camshaft position sensor.
Toyota Camry
2007-2024For Toyota Camry, P0397 is most commonly a direct failure of the camshaft position sensor itself, or a corroded connector due to engine bay heat and moisture.
65% fixed by replacing the camshaft position sensor.
Ford F-150
2004-2024On Ford F-150s, especially those with VCT (Variable Cam Timing), P0397 can indicate a failing sensor or a problem with the VCT solenoid wiring or the phaser itself, which can affect the sensor's reading.
50% fixed by replacing the camshaft position sensor.
Frequently Asked Questions
What does P0397 mean?
P0397 indicates that your vehicle's engine control module (ECM) is receiving a lower-than-expected voltage signal from the camshaft position sensor on Bank 2. This sensor tells the ECM the exact position of the camshaft, which is critical for engine timing and fuel injection.
Can I drive with P0397?
Yes, for short trips only. If your engine is running rough, stalling, or hard to start, limit driving to essential trips under 10 miles and avoid highways. If the engine stalls frequently or won't start, do not drive it.
Will P0397 clear itself?
No, P0397 will not clear itself. The engine control module stores this code until the underlying issue is resolved and the system passes its self-test, or until the code is manually cleared with a scan tool.
How do I fix P0397 myself?
Start by visually inspecting the Bank 2 camshaft position sensor and its wiring for damage. If no obvious issues, test the sensor with a multimeter. If the sensor tests bad, replace it. If the sensor is good, check the wiring for continuity between the sensor and the ECM.
How much does it cost to fix P0397?
A DIY fix for P0397 typically costs $70-$250 for a new camshaft position sensor. Professional repair at a shop usually ranges from $150-$500, including parts and labor.
P0397 keeps coming back - why?
P0397 often returns if the underlying wiring issue was not fully resolved, if a cheap aftermarket sensor was used, or if the problem is actually with the engine control module (ECM) or internal engine timing components.
Will P0397 fail emissions/smog test?
Yes, P0397 will cause your vehicle to fail an emissions or smog test. The Check Engine Light being on automatically results in a failure in most states, and this code directly impacts engine timing and emissions control.
What's the difference between P0397 and P0398?
P0397 indicates a "low input" signal from the Bank 2 camshaft position sensor, meaning the voltage is too low. P0398 indicates a "high input" signal, meaning the voltage is too high. Both point to a problem with the sensor circuit but describe different electrical conditions.
P0397 on Honda Accord?
On many Honda Accord models, P0397 can be caused by a failing camshaft position sensor, but also frequently by issues with the VTEC oil pressure switch wiring or the VTEC solenoid itself, which can indirectly affect camshaft timing signals.
Questions to Ask Your Mechanic
Did you check the wiring continuity between the sensor and the ECM?
Good answer: Yes, I tested all three wires for continuity and resistance, and they're all within spec. No shorts or open circuits.
What were the live data readings from the Bank 2 camshaft position sensor?
Good answer: The sensor was showing a flat line or erratic signal when cranking, indicating it's not sending a proper pulse. The voltage was consistently below the specified threshold.
Repair Cost Estimate
DIY Repair
Parts only
$70-$250
Shop Repair
Parts + labor
$150-$500
Save $80-$250 by doing it yourself
Difficulty
intermediate
Time
1-3 hours
Intermediate - requires a multimeter and some electrical diagnostic skills beyond basic part replacement.
Cost of Waiting
Ignoring P0397 can lead to severe engine performance issues, including stalling, hard starting, or a no-start condition. Continued driving with an incorrect camshaft signal can cause incorrect fuel injection and ignition timing, potentially leading to misfires, reduced fuel economy, and increased emissions.
While You're In There...
Apply to the electrical connector pins to prevent corrosion and ensure a good electrical connection, especially in engine bay environments.
If you find any frayed or damaged wires near the sensor, repairing them properly with a kit ensures a lasting fix and prevents future electrical issues.
Tools You'll Need
- OBD-II Scan Tool
- Basic Socket Set
- Screwdrivers
- Multimeter
- Wire Strippers/Crimpers (if wiring repair is needed)
- Electrical Tape or Heat Shrink Tubing (if wiring repair is needed)
P0397 is a common sensor code. Most repairs involve replacing the camshaft position sensor, which is a straightforward job for an intermediate DIYer, and your engine will run smoothly afterward.
- Family-owned since 1957
- 990,000+ happy customers
- Fast nationwide shipping
- Easy returns
Your Next Steps
Step 1: Visually inspect the Bank 2 camshaft position sensor's wiring and connector for any damage, corrosion, or looseness. Ensure the connector is fully seated.
Step 2: If the visual inspection doesn't reveal the problem, use a multimeter to test the sensor's resistance and the voltage at its connector. Compare readings to your vehicle's service manual specifications.
Step 3: If the sensor tests faulty, replace the Bank 2 camshaft position sensor. If the wiring is damaged, repair it using appropriate connectors and heat shrink tubing.