CODE MEANING AND SEVERITY
Code meaning: P0345 is the diagnostic trouble code for the Camshaft Position Sensor A Circuit (Bank 1) fault. In inline-four Honda Civics (2022–2024), there is typically one camshaft position sensor circuit used for the engine’s cam timing signal. P0345 indicates an abnormal condition in the camshaft position sensor circuit A, which can be caused by a faulty sensor, wiring harness fault, poor connector connection, or, in some cases, a timing-related issue that affects the sensor signal.
Data status and recalls: Based on the provided NHTSA data for 2022–2024 Honda Civic, there are no owner complaints and no official recalls documented for this issue in the database. No recalls found in NHTSA database.
Severity and impact: P0345 is a powertrain/engine management DTC. It can cause symptoms ranging from a rough idle or poor engine performance to a no-start condition or stall in some cases. If the cam signal is not detected properly, the PCM may retard or advance timing or limit engine power to protect the engine, which can leave you stranded in certain situations. In general, treat P0345 as a serious issue that should be diagnosed and repaired promptly to avoid possible misfire, reduced drivability, or engine damage.
COMMON CAUSES ON HONDA CIVIC
- Faulty camshaft position sensor (sensor A) itself.
- Damaged or corroded sensor connector, or a loose/worn harness connection to the sensor.
- Wiring faults in the camshaft sensor circuit (open circuit, short to ground, or short to 5V/reference line).
- Oil leaks or heavy oil contamination around the sensor housing (oil can interfere with the sensor’s signal or wiring).
- Timing chain wear/stretch, misalignment, stretched tensioner, or timing components that affect the cam position signal.
- PCM/ECU fault or intermittent communication with the cam sensor (less common).
- Sensor circuit reference/ground faults or noise in the system.
Note: In the Civic’s inline-four configuration, there is typically a single primary camshaft sensor circuit (no “Bank 2” in the same sense as multiple-bank V8 engines), so P0345 generally references the primary Camshaft Position Sensor A circuit for Bank 1.
SYMPTOMS
- Check Engine Light (CEL) illumination.
- Rough idle or unstable idle.
- Hesitation, misfire, or reduced engine power during acceleration.
- Stalling or difficulty starting (no-start can occur in some cases).
- Reduced fuel efficiency or erratic engine performance.
- In some cases, no noticeable symptoms aside from a stored code and possibly a limp-home mode.
DIAGNOSTIC STEPS
What you’ll need: OBD-II scanner, basic hand tools, multimeter, service manual wiring diagram for the CPS circuit (Camshaft Position Sensor A), and optionally a scan tool with real-time cam signal data or an oscilloscope.
Step 0: Verify the code and history
- Confirm P0345 is current (not a one-time historic code) and note any freeze-frame data, RPM, engine temperature, and whether the vehicle stalls or runs poorly.
Step 1: Visual inspection
- Inspect the camshaft position sensor and its connector for damage, corrosion, or oil contamination.
- Check the wiring harness for cracked insulation, stretched conduits, or chafed wires near hot components or moving parts.
- Look for oil leaks around the sensor area or valve cover where oil could contaminate the sensor.
Step 2: Check sensor connections and harness integrity
- Disconnect the sensor connector and inspect pins for corrosion or bent pins; reseat firmly.
- Look for pulled or damaged wires at the connector and along the run to the PCM.
- Clean the connector contacts if there is light corrosion (use electrical contact cleaner and ensure a dry, tight connection).
Step 3: Inspect for mechanical timing issues
- If there are symptoms of timing-related problems (unusual noises, severe power loss, or persistent misfire), verify timing.
- For many Civics, timing components are a chain-driven setup; verify timing marks if you have the tools and expertise. A timing issue can cause cam sensor misreads or loss of proper signal.
- Perform a compression test if timing concerns are suspected: low compression on one or more cylinders can accompany cam-position issues.
Step 4: Electrical tests for the CPS circuit (use wiring diagram)
- With the ignition off, check resistance between the CPS signal wire and ground; check resistance between the CPS power/reference wire and 5V reference (or as specified by the service manual). Note that many cam sensors are Hall-effect devices; resistance values may not be meaningful, so rely on voltage and signal testing rather than pure ohms.
- With the ignition ON (engine NOT running) check that the sensor receives the proper reference voltage (usually a 5V reference from the PCM) and that the ground is solid.
- Reconnect the sensor and use a scan tool to monitor the camshaft position sensor signal in real time while cranking and/or running. The sensor should produce a clean, regular pulsed signal that changes with RPM. If there is no signal or it looks erratic, suspect the sensor or the wiring.
Step 5: Live data and diagnostics
- Use a compatible scanner to observe Camshaft Position Sensor A signal (and the Crankshaft Position Sensor, if available) during engine cranking and running.
- If the CPS signal is missing or erratic and wiring checks are clean, replace the camshaft position sensor.
- If the CPS signal looks good but the PCM still logs P0345, suspect a PCM fault (rare). In such a case, perform additional diagnostics or consult a dealer.
Step 6: Post-repair checks
- After any sensor or wiring repair, clear the codes and perform a road test to verify that the code does not return.
- Re-check for vacuum leaks, misfires, or other codes that could indicate related problems (P0300–P0306 for misfires, P0011/P0012 related to VVT if applicable).
RELATED CODES
- P0340: Camshaft Position Sensor Circuit Malfunction (general)
- P0341: Camshaft Position Sensor Circuit Range/Performance (Bank 1 or sensor A)
- P0342: Camshaft Position Sensor Circuit Low Input (Bank 1 or sensor A)
- P0343: Camshaft Position Sensor Circuit High Input (Bank 1 or sensor A)
- P0335: Crankshaft Position Sensor A Circuit
- P0336: Crankshaft Position Sensor Range/Performance
- P0330-P0334: Other crank/cam or wiring related codes (context-dependent)
- P0300-P0306: Random/Multiple misfire if cam timing or signal is absent or erratic
REPAIR OPTIONS AND COSTS (2025 PRICES)
Note: Actual prices vary by region, shop, and whether OEM or aftermarket parts are used. The ranges below are rough estimates to help budgeting.
Camshaft Position Sensor A (sensor alone)
- Parts: $15–$150 (aftermarket vs OEM)
- Labor: $40–$120
- Typical job total: $100–$270
Camshaft position sensor harness/connector repair
- Parts: often none or small wiring harness pigtail cost
- Labor: $60–$150
- Typical job total: $100–$250
Sensor replacement with no other issues
- Typical total: $100–$350 (parts + labor)
Timing chain/tensioner or related timing component service
- If a timing issue is found or suspected (e.g., chain stretch, tensioner wear)
- Parts: $200–$600 (chain, guides, tensioner, gaskets)
- Labor: $600–$1,400
- Typical job total: $800–$2,000+
- Note: Timing component work is mechanical and more intensive; exact price depends on engine layout and whether additional components must be replaced.
PCM/ECU replacement (rare)
- Parts: $200–$900 (depends on OEM vs aftermarket)
- Labor: $150–$400
- Typical job total: $350–$1,300
- Typically considered only after other causes are ruled out and if the PCM is confirmed faulty.
Ongoing maintenance or incidental costs (optional)
- Cleaning or replacing related sensors or adapters
- Additional tests or diagnostics by a professional
DIY VS PROFESSIONAL
DIY-friendly steps (for confident hobbyists)
- Visual inspection of sensor and wiring, cleaning corrosion, reseating connectors, and checking for obvious damage.
- Use a proper OBD-II scanner to confirm current code and monitor live cam signal data if you have access to a tool that displays sensor activity.
- Replacing the sensor is often doable with basic hand tools; ensure you follow the service manual for torque specs when reinstalling.
DIY limits and when to go pro
- If you discover timing chain wear or timing marks out of alignment, or if you cannot confidently diagnose electrical wiring faults, seek a professional.
- If the PCM might be at fault or you’re not obtaining clean sensor signals after sensor replacement and wiring checks, consult a technician.
- Timing chain-related service and PCM replacement are generally best left to a professional shop with the right expertise and proper timing alignment tools.
PREVENTION
- Regularly inspect the camshaft position sensor and its connector area for oil leaks, dirt, and corrosion; clean as necessary and ensure a solid connection.
- Keep the engine clean and free of oil leaks that could contaminate the sensor or its wiring.
- Use OEM- or manufacturer-recommended torque specs and connectors when servicing cam timing components.
- Address engine oil leaks promptly; oil contamination of the sensor can lead to erroneous readings or failure.
- If you perform any engine timing work, ensure proper timing alignment and verify compression to confirm correct timing.
- Periodically scan for and clear codes after any repair and confirm the issue does not recur with a road test.
Important data caveats and data limitations
- Data status: The provided real-world data for 2022–2024 Honda Civic shows no owner complaints and no recalls in the NHTSA database specifically tied to P0345 for this model/year.
- This guide uses general automotive knowledge for diagnosing camshaft position sensor circuit faults and is not a substitute for vehicle-specific service information. If you have a persistent or escalating issue, consult a qualified technician.
- If service manuals or OEM TSBs become available for this model/year in the future, follow those official instructions and torque specs rather than the general guidance provided here.