Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble with a sensor that helps it know where the engine parts are. It's like if your GPS stopped working and you didn't know what street you were on.
The P1397 code is triggered when the Engine Control Module (ECM) detects a problem with the camshaft position sensor 'B' circuit on bank 1.
The camshaft position sensor monitors the position of the camshaft and sends this information to the ECM. The ECM uses this data to control the timing of the engine's fuel injection and ignition systems. A malfunction in this sensor or its circuit can cause the engine to run poorly or not start at all.
• Check Engine Light is on
• Engine misfires or runs rough
• Poor fuel economy
• Faulty camshaft position sensor
• Wiring issues in the sensor circuit
• ECM malfunction
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Scan the vehicle for codes and freeze frame data
• Inspect the camshaft position sensor and its wiring
• Test the sensor using a multimeter
• Replace the camshaft position sensor
• Repair or replace damaged wiring
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regular maintenance and inspection of sensors
• Keep the engine clean and free of debris
• Ensure proper electrical connections
Sensor Issue
• Have the vehicle diagnosed by a professional
• Avoid driving the vehicle if it runs poorly
Check with your vehicle manufacturer for warranty coverage on sensors.
This code is commonly associated with BMW vehicles and often relates to sensor failure or wiring issues.
Moderate – It should be addressed soon to avoid further engine problems.
Driving with a malfunctioning sensor can lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Vehicle in a safe environment for testing
The camshaft position sensor is typically located near the top of the engine, close to the camshaft.
Q: Can I drive with a P1397 code?
A: It's not recommended to drive for long periods with this code, as it can lead to engine performance issues.
Q: How do I know if my camshaft position sensor is bad?
A: Common signs include engine misfires, rough idling, and poor fuel economy.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
View on Amazon
Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
View on Amazon
Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.
Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
View options on Amazon
Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.