P0345 Code: Honda Accord (2018-2023) - Causes, Symptoms & Fixes

Diagnostic guide: OBD2 code P0345 on 2018-2023 Honda Accord

Note on data limitations

• In the supplied NHTSA data for Honda Accord (2018-2023), there are no owner complaints for this exact issue and no official recalls found. No recalls found in NHTSA database. This guide uses general automotive knowledge for technical explanations while clearly noting the data limitations.

CODE MEANING AND SEVERITY

• Code meaning: P0345 stands for Camshaft Position Sensor A Circuit Malfunction. It indicates the Powertrain Control Module (PCM) detects an incorrect or out-of-range signal from the camshaft position sensor “A” circuit.
• Honda specifics: On many Honda 4-cylinder engines in the Accord, the camshaft position sensor is the primary cam sensor (sensor A). The PCM uses this sensor signal to synchronize the ignition and fuel-injection timing with the camshaft position.
• Severity: Moderate to severe. This code can cause misfires, poor drivability, stalling, or no-start situations. If left unresolved, it may lead to increased emissions or damage in timing-related systems. Because the cam sensor provides essential timing information, intermittent sensor signals can create drivability issues even if the vehicle runs.

COMMON CAUSES ON HONDA ACCORD

• Faulty camshaft position sensor (sensor A) itself
• Damaged, corroded, loose, or unseated sensor electrical connector or wiring harness (grounds, power feed, or signal circuit)
• Short to ground, short to voltage, or high resistance in the cam sensor circuit
• Oil or debris contamination around the sensor or connectors (common with leaks near the cylinder head)
• Broken or frayed wiring harness routes (chafing on the timing cover or engine block)
• 5V reference or ground issues from the PCM (less common, but can cause intermittent sensor readings)
• Timing-related issues that affect sensor readings (rare; e.g., timing chain tensioner/slack or valve timing concerns) that alter cam position perception
• PCM/ECU fault (rare; usually a last resort after other causes are ruled out)

SYMPTOMS

• Check Engine Light (CEL) or MIL illuminated
• Engine stumbles, misfires, or runs roughly at idle or under load
• Reduced power or limp-home mode in some scenarios
• Hard starting or no-start in some cases
• Intermittent drivability problems (especially after engine warmth or under specific RPM ranges)
• Occasional rough idle that improves after a short drive (if sensor signal stabilizes)

DIAGNOSTIC STEPS

Note: Perform steps with appropriate safety precautions. If you’re not comfortable with electrical wiring checks, seek professional help.

A. Prepare and verify

• Scan for codes with a reliable OBD-II scanner and record freeze-frame data.
• Note any related codes (P0340, P0341, P0335, P0336, P0337, or misfire codes P0300-P0308) for correlation.
• Check battery health and charging system; a weak battery can cause odd sensor readings.

B. Visual inspection

• Inspect camshaft position sensor and its wiring harness for damage, oil leaks, or contamination.
• Check the sensor connector: corrosion, bent pins, loose latch, or poor clamp tension. Disconnect and reconnect to reseat.
• Look for worn or damaged harness insulation, especially where the harness passes near the timing cover or heat sources.
• Verify that the sensor is properly seated in its mounted hole and not cross-threaded or loose.
• Inspect related circuits (ground points and 5V reference path) for signs of corrosion or damage.

C. Electrical testing (use DVOM or oscilloscope if available)

• 5V reference and ground:
  • With ignition ON (engine OFF), test the cam sensor connector pins for proper 5V reference and ground. The engine ECU provides a 5V reference to the sensor; a missing or flaky reference can cause P0345.
  • Check continuity from sensor to PCM ground; look for high resistance that could indicate a loose connection or damaged wire.
• Sensor signal circuit:
  • With the engine OFF, check continuity between the sensor signal wire and PCM input. Verify no shorts to power or ground.
  • With the ignition ON and engine cranking or at a provoked RPM (as per service manual), monitor the sensor signal voltage:
    • For a Hall-effect type cam sensor (common on Hondas), the signal will switch with RPM. You should see a clean, non-flat waveform or a logical voltage transition when rotated. Absence of signal or a constantly high/low value indicates a faulty sensor or wiring issue.
  • If an oscilloscope is available, view the cam sensor waveform while cranking or running. A distorted, intermittent, or no waveform is a strong indicator of sensor or wiring fault.
• Resistance checks:
  • Check the sensor’s resistance specification per the service manual (for the specific engine variant). Compare to OEM spec. Significant deviation suggests a faulty sensor.
  • If available, check connector pins for excessive resistance or short to adjacent pins.

D. Related checks

• Compare with crankshaft position sensor (P0335 or similar) signals if you have access to a scope. A significant phase or timing discrepancy between cam and crank signals can indicate timing issues or sensor faults.
• Inspect the timing components only if there is suspicion of timing chain/belt slack or mis-timing (e.g., unusual mechanical noises, severe drivability change). If the timing has jumped, cam position sensor readings will be unreliable.
• Consider replacing the camshaft position sensor if tests indicate a fault, or if the sensor shows mechanical damage, oil ingress, or a degraded signal.
• If wiring and sensor test pass but the code persists, consider PCM fault or software calibration; reflash or update might be required per service bulletin, though no recalls/TSBs are shown in the provided data.

E. Post-repair tests

• Clear the DTCs and perform a road test or drive cycle to verify that P0345 does not return.
• Recheck for any additional codes that may appear after the repair.
• Confirm no oil leaks near the sensor area to prevent recontamination.

RELATED CODES

• P0340: Camshaft Position Sensor Circuit Malfunction (general/Bank 1 A)
• P0341: Camshaft Position Sensor Circuit Range/Performance (Bank 1 A)
• P0335: Crankshaft Position Sensor A Circuit Malfunction
• P0330, P0331, P0332, etc. (crank sensor family issues) if crank/cam correlation is suspected
• P0300-P0308: Random/Misfire codes that may accompany cam sensor faults
  Note: In practice, P0345 is often checked alongside P0340/P0341 to determine if the issue is sensor-only or a more complex timing-related problem.

REPAIR OPTIONS AND COSTS (2025 PRICES)

Important: No recalls found in NHTSA database for this model/year and issue in the provided data. The following are typical repair cost ranges based on common industry pricing (not a guarantee of local shop pricing).

• Camshaft Position Sensor (OEM or aftermarket) replacement

  • Parts: roughly $40–$150
  • Labor: about 0.5–1.5 hours
  • Estimated total: $100–$350 (depending on region and labor rate)

• Sensor harness/connector repair or replacement (if wiring is damaged)

  • Parts: usually $10–$60 for connectors; wiring repair materials as needed
  • Labor: 0.5–2 hours
  • Estimated total: $100–$400

• Timing-related repair (rare; e.g., timing chain tensioner or related components if chain slack caused sensor misreadings)

  • Parts: $150–$900 (or more for OEM timing kit)
  • Labor: 3–8 hours depending on engine variant and accessibility
  • Estimated total: $500–$2,500

• PCM or software reflash/update (rare)

  • Parts: usually included in labor if no replacement needed
  • Labor: 1–2 hours
  • Estimated total: $150–$500 (software/service charge)

• Diagnostic fee (if performed by a shop)

  • Typical range: $80–$150 (sometimes waived with repair)

Notes:

• The above ranges assume typical 1.5L or 2.0L Honda Accord engines in the 2018–2023 window and general market pricing. Actual costs vary by region, shop, and whether OEM or aftermarket parts are used.

DIY vs PROFESSIONAL

• DIY pros:
  • If you have a reliable scan tool, basic electrical testing gear (multimeter, possibly oscilloscope), and comfort with wiring inspections, you can perform visual inspection and some electrical checks.
  • You can replace the camshaft position sensor yourself if you locate it and confirm it’s accessible, and if you can reseat the connector and clear codes.
• DIY cons:
  • Electrical diagnostics can be tricky; a bad test can lead to unnecessary part replacement.
  • Some Hondas place the cam sensor in a tight area near the timing cover; reaching it may require removal of ancillary parts or the engine cover.
• Professional:
  • A technician can accurately diagnose sensor vs wiring vs timing issues, perform precise 5V reference checks, and interpret waveform data with an oscilloscope.
  • They can rule out PCM faults and perform software updates if needed, with proper service information.
• Time consideration:
  • Simple sensor replacement: about 0.5–1.5 hours
  • Wiring repairs or timing-related service: 1–6+ hours depending on access and complexity

PREVENTION

• Regular maintenance to minimize oil leaks near the sensor area: fix oil leaks promptly to prevent sensor contamination.
• Use high-quality oil and a clean, properly sealed oil system to reduce seepage and debris around the sensor.
• Keep electrical connections clean and dry; inspect the cam sensor connector for corrosion during routine service.
• When performing timing service or VVT tasks, use the correct torque specs and ensure proper alignment to avoid sensor displacement or signal anomalies.
• If you replace any cam/valve timing components, consider replacing related sensors/wiring if the harness shows signs of wear.
• Software/ECU updates: ensure the PCM software is up to date if the dealership has issued non-recall service updates for cam timing synchronization.
• Vigilance for symptoms: address rough idle, misfires, or drivability issues promptly to prevent possible downstream damage.

Final notes

• This guide follows the data you provided: no recalls found in the NHTSA database for this make/model/year and issue, and no complaints recorded in the supplied data. Use this guide as a diagnostic framework, but rely on your own vehicle data and technician assessments for final repair decisions.
• If you have access to vehicle service information or Technical Service Bulletins (TSBs) from Honda for your exact VIN, consider them as well, since they may provide model-specific steps or cautions that aren’t reflected in the data above.