P0345 Code: Toyota Tacoma (2016-2023) - Causes, Symptoms & Fixes

CODE MEANING AND SEVERITY

• Code: P0345
• Full meaning: Camshaft Position Sensor “A” Circuit Malfunction (Bank 1) / Sensor A circuit issue for the camshaft position sensor on engines with dual camshafts. On the Toyota 2016–2023 Tacoma (3.5L V6 DOHC), this typically refers to the primary camshaft position sensor circuit used by the PCM to reference cam timing. The exact bank designation (“A” vs. “B”) can vary by engine and diagnostic terminology; in practice, P0345 indicates a problem with the Camshaft Position Sensor circuit that the PCM cannot trust.
• Severity: Moderate to high. It can cause misfires, poor driveability, stalling, or no-start conditions. In many cases you’ll see the Check Engine Light and a limp/rough-running condition until the fault is corrected.
• Data note: No recalls found in NHTSA database for this make/model/year/issue combination. No owner complaints in the provided dataset. Data limitations mean prevalence and causal strength cannot be inferred from this dataset alone; use the steps below as a general diagnostic guide for this code.

COMMON CAUSES ON TOYOTA TACOMA

• Faulty Camshaft Position Sensor (CMP sensor A)
  • Sensor inside the cam gear/valve cover may fail or deteriorate over time.
• Wiring harness or connector problems
  • Damaged, frayed, or corroded wires; loose or dirty connectors; poor seal allowing moisture.
• Oil contamination or contamination of sensor area
  • Oil leaks or sludge can affect sensor performance or wiring insulation.
• Timing-related issues
  • Timing chain tensioner/guide wear, or variable valve timing (VVT) phaser problems that affect cam timing signals.
• PCM/ECU fault (less common)
  • Rare, but possible if the processor misreads or loses the sensor signal.
• Ground/Power supply problems
  • Faulty ground path or 5V reference supply to the CMP sensor.
• Other related sensors
  • Crankshaft Position Sensor (CKP) issues can surface as cam signal faults or create misleading data flows in the PCM.

SYMPTOMS

• Check Engine Light (MIL) illuminated.
• Engine runs poorly: misfires, rough idle, hesitation, or stumbling.
• Reduced power or acceleration, possible limp mode in some cases.
• Difficult starting or intermittent no-start conditions.
• Decreased fuel economy.
• Intermittent stalling or bucking, particularly at idle or low RPM.
• No obvious mechanical noise; electrical fault symptom is more common.

DIAGNOSTIC STEPS

Important: Start with a thorough visual and data-based approach, then perform targeted electrical tests. If you’re unsure, consult a professional.

Step 0 – Gather and verify

• Use a quality OBD-II scanner to confirm P0345 and capture freeze frame data.
• Note any related codes (P0340, P0341, P0342, P0344, etc.) that may accompany P0345.

Step 1 – Visual inspection

• Inspect CMP sensor(s) and wiring harnesses for damage, oil leaks, or contamination near the cam cover.
• Check sensor connectors for corrosion, bent pins, or loose locking tabs.
• Check for oil leaks around the cam area that could contaminate the sensor or wiring.

Step 2 – Verify power, ground, and reference signals

• Locate the CMP sensor connector and back-probe to access: 5V reference, ground, and signal wire.
• With the ignition on (engine OFF but powered), verify:
  • 5V reference at the CMP sensor pin (near 5V, not 0V or 12V).
  • A solid ground path on the sensor ground pin.
• Turn the ignition OFF, then disconnect the CMP sensor and measure resistance across the sensor’s signal and ground? (If the service manual provides resistance specs for the specific sensor, compare.) In many cases, you’ll test by checking back-probed voltages once the engine is cranking/starting.

Step 3 – Signal interpretation (with scope or graphing tool)

• If you have an oscilloscope or a graphing multimeter, monitor the camshaft position sensor signal while cranking and running.
• Expect a clean, repeatable digital square-wave pattern or a clear pulsed signal depending on sensor type.
• If there is no signal, a weak/erratic signal, or an inverted/altered pattern, suspect CMP sensor, wiring, or PCM input path.

Step 4 – Rule out the crank position sensor and relative timing inputs

• If the CKP sensor data appears healthy but P0345 persists, re-check the CMP circuit specifically. Inconsistent CKP data can influence PCM timing logic and create false cam-signal faults.
• If feasible, compare sensor readings to service manual specifications for timing, or use scan data to observe actual cam phasing vs. crank reference as the engine runs.

Step 5 – Mechanical timing check (consider if electrical tests are inconclusive)

• For interference engines like the 3.5L V6, verify timing chain/belt alignment marks and tensioners if you have reason to suspect timing wear or chain slack.
• Cam timing misalignment can trigger cam sensor circuit faults because the PCM detects a discrepancy in cam timing reference signals.

Step 6 – Inspect or test for oil contamination and sensor condition

• If the sensor is oily or contaminated, replace the sensor and clean the surrounding area.
• Ensure the sensor mounting surface is clean and free of oil, and reseal the cover as appropriate.

Step 7 – Replace CMP sensor or repair wiring as needed

• If the CMP sensor tests out of spec or a repeatable fault remains after wiring check, replace the CMP sensor.
• If wiring or connection faults are found, repair or replace the affected harness/conductor, then retest.

Step 8 – Clear codes and road test

• After repair, clear the codes and perform a road test to confirm the fault is resolved and that no new codes reappear.

Notes:

• If you do timing work, ensure you have the correct timing procedure per Toyota service information for the 3.5L V6 Tacoma.
• When replacing the CMP sensor, use the correct Toyota OEM or equivalent sensor for your engine and model year.

RELATED CODES

• P0340 Camshaft Position Sensor Circuit Malfunction (Bank 1)
• P0341 Camshaft Position Sensor A Circuit Range/Performance
• P0342 Camshaft Position Sensor A Circuit Low Input
• P0344 Camshaft Position Sensor Intermittent
• Other P034x codes may appear if there are cascading issues in the cam/crank timing circuits or PCM data interpretation.

REPAIR OPTIONS AND COSTS (2025 PRICES)

Prices vary by region, shop, and whether you use OEM parts. The ranges below reflect typical US market pricing as of 2025 and are for reference only.

A. Camshaft Position Sensor (CMP Sensor) replacement

• Parts: $20–$120 (aftermarket); $60–$150 (Toyota OEM)
• Labor: 0.5–1.0 hours (depending on access); $70–$180 per hour
• Estimated total: $110–$260 (aftermarket sensor) or $230–$380 (OEM sensor)

B. CMP Sensor wiring/connector repair

• Parts: minor (wiring harness rework may be included)
• Labor: 0.5–1.5 hours
• Estimated total: $100–$350 depending on extent of repair

C. Timing-related repair (if mechanical timing is involved)

• Timing chain/belt kit, tensioners, guides, seals
• Parts: $200–$700 (timing kit and seals; Toyota OEM higher)
• Labor: 6–12 hours depending on engine access
• Estimated total: $1,000–$3,000+ (often closer to $1,500–$2,900 excluding incidental repairs such as gaskets)

D. PCM/ECU replacement (rare)

• Parts: $300–$800 (rebuild/used units may be cheaper)
• Labor: 1–3 hours
• Estimated total: $500–$1,800

E. Miscellaneous costs

• Diagnostic fees if performed at a shop: $80–$150+
• OE sensor variants or dealer-specific pricing: adjust accordingly

Note: If the fault is intermittent or caused by a poor connection rather than a failed sensor, costs can be much lower than a full sensor replacement.

DIY vs PROFESSIONAL

• DIY feasibility: Moderate to high for a typical front-engine CMP sensor replacement on many Tacomas. If the CMP sensor is easily accessible on your engine, you can replace it with basic hand tools. You’ll need to locate the sensor, disconnect the connector, remove a mounting bolt, swap sensors, and reconnect. Replacing may void? No. Just ensure proper torque on the sensor and that the sensor electrical connector is clean and securely seated.
• Advantages of DIY: Lower cost, quick turnaround, learning opportunity.
• Risks of DIY: Incorrect torque, damaged connectors, poor wiring, misdiagnosis of timing issues, and not addressing a deeper mechanical problem. If timing components or a PCM issue is suspected, professional service is strongly recommended.
• Professional considerations: A shop can perform electrical diagnostics with a scope/scan tool, verify timing, and perform any necessary timing-related repairs safely, with proper torque specs and service procedures.

PREVENTION

• Regular oil changes with the correct API/ACEA grade and Toyota-recommended oil to maintain VVT and sensor health. Poor oil quality or low oil level can affect VVT operation and cam timing signals.
• Use high-quality filters and OEM-recommended oils to prevent varnish/sludge buildup in the camshaft area and sensor surfaces.
• Inspect and replace worn wiring harnesses near the engine when signs of wear or chafing appear; protect wiring from heat and moisture.
• Keep engine timing components in good condition; if you have high-mileage engine or signs of timing wear, address timing chain/tensioners per Toyota service guidelines before a sensor fault becomes critical.
• Ensure temperature and moisture protection for electrical connectors; use corrosion-resistant connectors or dielectric grease as appropriate.
• If you’ve had any previous cam or crank sensor faults, consider a thorough inspection of related VVT components (solenoids, oil passages, and related seals).
• Respond promptly to any MIL/MACK if P0345 or related codes reappear; early repair can prevent more severe drivability issues.

Data limitations and notes

• The provided dataset indicates no recalls and no NHTSA complaints for this exact make/model/year/issue combination. This guide uses general automotive knowledge and Toyota Tacoma specifics to outline typical failure modes, steps, and costs. Real-world frequency and outcomes may differ. Always refer to the official Toyota service information for exact torque specs, wiring diagrams, bank designations (A/B), and diagnostic procedures for your particular VIN and engine version.

If you’d like, I can tailor this guide to your exact Tacoma version (VIN, engine build week, or whether you’ve got the 2GR-FKS 3.5L V6 with VVT) and provide a focused step-by-step diagnostic worksheet you can print or save.