How to Fix Diagnostic Code P1345

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🚨 Diagnostic Profile

Vehicle Make: Chrysler

Description: CKP/CMP Correlation. Crankshaft Position (CKP) and Camshaft Position (CMP) sensor signals are not correlating with each other, indicating a timing relationship fault between the crankshaft and camshaft reference signals.

🚨 Repair Difficulty Tier

Tier: [Intermediate]

Diagnosis requires scope or oscilloscope-level signal analysis and mechanical timing verification. Sensor replacement is straightforward, but correlation faults are often caused by timing belt or chain stretch, reluctor ring damage, or sensor misalignment, which require deeper inspection.

🛠️ Resolution Steps

Step 1: Preliminary Inspection

  • Verify battery state of charge and charging system output using a digital multimeter; confirm cranking voltage does not drop excessively and charging voltage stays within normal alternator output range with engine running.
  • Inspect the CKP sensor connector and harness for corrosion, pin damage, or loose fit at the sensor location on the engine block or bellhousing, depending on engine family (most Chrysler V6/V8 and 4-cylinder engines locate the CKP near the crankshaft pulley or transmission bellhousing).
  • Inspect the CMP sensor connector and harness for corrosion, pin damage, or loose fit at the sensor location, typically mounted at the front of the cylinder head or timing cover near the camshaft sprocket.
  • Check sensor mounting bolts for proper torque and secure installation; confirm no play or looseness at the mounting boss.
  • Inspect the crankshaft reluctor/trigger wheel (tone wheel) for missing teeth, cracks, or metal debris accumulation at the crank sensor reluctor, typically integrated onto the crank sprocket or balancer/flexplate.
  • Inspect the camshaft target/tone wheel for damage, oil contamination, or debris buildup at the camshaft sprocket or phaser assembly.
  • Review freeze frame data and all stored DTCs using a capable OBD-II scan tool; note engine RPM, load, and coolant temperature at the time the correlation fault was set.

Step 2: Diagnostic Verification

  • Confirm live CKP and CMP sensor waveforms using a lab oscilloscope; most Chrysler CKP sensors are Hall-effect or variable reluctance type producing a digital square wave or AC sine wave pattern — verify consistent pulse spacing with no dropouts, missing teeth signatures, or erratic voltage spikes at cranking and idle speeds.
  • Verify the crankshaft-to-camshaft timing relationship by checking timing belt or chain alignment against factory timing marks (cam sprocket dowel/dot alignment with chain link plating, and crank keyway alignment with block or cover timing marks per service manual).
  • Check for timing chain/belt stretch using a manufacturer-specified timing chain stretch measurement procedure (many Chrysler PCMs support a Cam/Crank timing correlation PID or chain wear percentage reading via scan tool on newer engines with Variable Valve Timing).
  • Inspect timing chain tensioner, guides, and tensioner arm for wear, cracking, or hydraulic tensioner bleed-down.
  • Verify sensor air gap and mounting depth against OEM service specification; many Chrysler CKP/CMP sensors are non-adjustable pedestal-mounted units where air gap is fixed by design — confirm sensor fully seats against its mounting boss with no shims missing.
  • Perform a cylinder relative compression test or running compression/leak-down test if mechanical timing is confirmed correct but the correlation fault persists, to rule out internal valvetrain component failure (bent valve, worn lobe, or jumped tooth not visually obvious).
  • Clear codes and perform a controlled test drive or idle/rev test to confirm whether the correlation fault recurs under load and varying RPM conditions.

Step 3: Resolution & Reset Process

  • Replace the faulty CKP or CMP sensor, or the reluctor/tone wheel assembly, as identified during verification, using OEM or OEM-equivalent components to ensure correct signal amplitude and air gap tolerance.
  • Correct timing chain or belt installation, tension, or alignment if mechanical timing is found out of specification; replace chain, guides, tensioner, and sprockets as a complete kit when stretch or wear is confirmed, rather than replacing individual worn components.
  • Clear all stored DTCs with a scan tool and perform any applicable crankshaft/camshaft correlation relearn, variant learn, or PCM idle relearn procedure called for in Chrysler service information for the specific engine family (some Chrysler PCMs require a key-cycle relearn or a guided idle relearn after sensor or timing component replacement).
  • Road test the vehicle through a full drive cycle encompassing idle, steady-state cruise, and deceleration to verify the correlation fault does not return and no pending codes are set.
  • Document all measured waveform values, timing verification results, and replaced components in the service record for warranty and future diagnostic reference.

📦 Parts, Labor, and Budget Estimates

Required Components/Software:

  • CKP sensor (OEM or OEM-equivalent, engine-specific)
  • CMP sensor (OEM or OEM-equivalent, engine-specific; some Chrysler engines use dual CMP sensors on each bank)
  • Timing chain kit (chain, tensioner, guides, sprockets) if mechanical timing is out of specification
  • Factory-level or professional-grade bi-directional scan tool capable of correlation relearn/variant learn procedures (e.g., Chrysler/FCA-compatible diagnostic software such as wiTECH for dealer-level relearns, or a comparable aftermarket scan tool with OEM-level functions)
  • Digital storage oscilloscope for waveform verification

Average Component Price:

  • CKP sensor: approximately $40–$120 (part only)
  • CMP sensor: approximately $50–$150 per sensor (part only; some V6/V8 engines use two)
  • Timing chain kit: approximately $150–$450 (part only), depending on engine family and whether it includes variable valve timing phasers/solenoids
  • Dealer-level diagnostic software/subscription access (if required for relearn): approximately $50–$100 for a short-term subscription at independent shop level, or included in dealer diagnostic labor rate

Estimated Labor Hours:

  • Diagnosis and verification (waveform capture, timing inspection, freeze frame review): approximately 1.0–2.5 hours
  • CKP or CMP sensor replacement only: approximately 0.3–1.5 hours per sensor, depending on sensor accessibility (some CMP sensors on OHC engines are easily accessible; CKP sensors behind the harmonic balancer or inside the bellhousing require significantly more time)
  • Timing chain/belt system replacement (chain, guides, tensioner, sprockets): approximately 3.0–8.0 hours, depending on engine configuration (inline-4 front-timing-cover jobs are quicker; V6/V8 engines with dual timing chains or variable valve timing phasers require significantly more teardown time)
  • Post-repair relearn/variant learn and verification road test: approximately 0.3–0.5 hours