Comprehensive diagnostic guide for OBD-II code P1335 Powertrain, crankshaft/camshaft position correlation

Scope and code context

• P1335 is a Powertrain Diagnostic Trouble Code (P-code) used in OBD-II diagnostics. P-codes are part of the powertrain category of codes that modern vehicles monitor to protect engine and emissions systems. They are generated when the PCM detects a parameter or sensor condition that indicates loss of proper coordination between critical timing sensors. (Source context: OBD-II Diagnostic Trouble Codes and Powertrain Codes discussions.)
• The exact fault definition for P1335 can vary by manufacturer; many references describe it as a crankshaft position-camshaft position correlation issue, i.e., the PCM is seeing CKP and CMP signals that do not align as expected. Always verify with vehicle-specific service information if available.

Symptoms

• MIL (Check Engine Light) illuminated, possibly with a "no-start" or difficult start condition
• Rough idle, engine stalling, misfires, or poor engine performance
• Harsh or intermittent loss of power, reduced drivability
• Crank/no-crank condition or hesitation during acceleration
• In some vehicles, quick reoccurrence of the MIL after clearing codes

Probable Causes

Note: These probabilities are approximate and vehicle-specific. Use them as a guide rather than absolute truth for a particular car.

• Crankshaft position (CKP) sensor fault or poor signal, including wiring/connector problems, reference voltage or ground issues
  • Estimated likelihood: 30-45%
• Camshaft position (CMP) sensor fault or poor signal, wiring/connector problems, or misadjusted timing reference
  • Estimated likelihood: 25-35%
• Timing system issue (timing belt/chain jump, worn tensioner, or a slipped belt/chain causing misalignment with CKP/CMP)
  • Estimated likelihood: 15-25%
• Wiring harness damage, corrosion, loose connectors, or poor grounds in CKP/CMP circuits
  • Estimated likelihood: 10-20%
• PCM/ECM fault or incorrect calibration (less common but possible, especially after repairs or software updates)
  • Estimated likelihood: 5-15%
• Oil intrusion or contamination on sensors, sensor backlash due to debris or bearing/reluctor ring issues
  • Estimated likelihood: 5-10%
• Other causes (rare): mechanical timing reference ( reluctor ring damage, cam/crank gear issues beyond sensor faults)
  • Estimated likelihood: 5-10%

Important safety notes

• Always follow safe procedures when working on ignition and timing systems. Disconnect the battery when disconnecting sensors or performing electrical testing to minimize risk of short circuits or unintentional engine cranking.
• If you must rotate the engine to inspect timing, ensure the vehicle is properly supported and in a safe state to avoid moving parts causing injury.

Tools Needed

• Diagnostic scan tool capable of live data and freeze-frame capture
• Digital multimeter (DVOM) for voltage and resistance checks
• Oscilloscope or a scope-capable multimeter (preferred) for CKP/CMP waveform verification
• Vehicle specific service information (FSM/TDX/TIS) for wiring diagrams, sensor reference voltages, and timing procedures
• Timing belt/chain inspection tools (as applicable)
• Basic hand tools and safety gear

Diagnostic procedure (step-by-step)

1) Confirm and document

• Retrieve the DTCs with an able scanner. Note any related codes, freeze-frame data, and ready/monitor status (emissions readiness).
• Confirm that the P1335 code is current and not just history data. Record vehicle VIN, engine type, RPM when the code appeared, and whether the MIL is on.

2) Visual and initial checks

• Inspect CKP and CMP sensor wiring harnesses for damage, loose connections, and grounds. Look for oil leaks or contamination around sensors, as oil can degrade sensor performance.
• Check for obvious mechanical timing issues: damaged/loose timing belt or chain tensioner, misaligned timing marks, or recent belt/chain work.
• Inspect reluctor rings, toothed wheels, and sensor mounting surfaces for damage or debris.

3) Electrical checks (sensor circuits)

• CKP and CMP reference voltage and ground: with ignition ON (engine off), verify that each sensor has proper reference voltage (typically 5V or 12V depending on system) and a solid ground. Check for wiring harness continuity and resistance to ground as specified by OEM diagrams.
• Check for corrosion, bent pins, or loose connectors; reseat connectors and re-test.
• If using a scope, inspect CKP and CMP signal waveforms while cranking. Look for:
  • Clean, consistent pulse trains with timing reasonable to engine speed
  • No dropped or irregular pulses
  • Proper phase relationship between CKP and CMP (as per OEM spec)

4) Mechanical timing check

• For engines with external timing belts/chains and a known correlation between CKP/CMP, verify timing alignment:
  • Rotate the crank by hand to align timing marks to factory spec
  • Inspect belt/chain condition and tensioners/ guides
  • If timing belt/chain slipped or jumped, correct timing and replace worn components
• If the engine uses only one sensor (some designs rely primarily on CKP with a redundant path), consult OEM guidance to confirm timing reference procedure.

5) Compression and mechanical integrity

• If timing appears correct and sensor signals are in spec, perform a cylinder compression test and leak-down test to rule out mechanical issues that could affect synchronization (e.g., bent valves, stuck lifters) that could produce correlation errors indirectly.

6) Verify sensor health and replace as needed

• If CKP or CMP signals are absent, irregular, or out of specification despite wiring checks, replace the faulty sensor(s) per OEM procedures.
• If a sensor is contaminated by oil or debris and cleaning is not effective, replacement is indicated.

7) Re-test after repairs

• Clear the codes, re-run the corresponding drive cycle, and monitor live data to confirm CKP and CMP signals are in sync and no new fault codes appear.
• Confirm that timing is correct and the engine runs smoothly without misfires or stalling.

8) Additional checks if the issue persists

• Check for software/PCM calibration updates for the vehicle model from the dealer, as occasionally a PCM calibration or software issue can present as a correlation fault.
• Inspect related systems that could influence timing signals, such as crankshaft reluctor ring damage, oil contamination, or sensor alignment changes due to maintenance work.

Repair approaches and likely fixes (order of preference)

• Most common fixes:
  • Replace CKP and/or CMP sensors that fail or produce degraded signals
  • Repair or replace damaged wiring, connectors, or grounds in CKP/CMP circuits
  • Correct timing belt/chain when found out of timing or damaged
• Less common but possible fixes:
  • PCM/ECM software update or replacement if OEM guidance supports this
  • Sensor contamination cleanup only if sensor is otherwise healthy

Documentation and testing after repair

• After repairs, clear codes and perform a careful road test or a defined drive cycle to verify that the code does not return.
• Review freeze-frame data and any reoccurring patterns to confirm the root cause was addressed.

Manufacturer Notes

• P1335 meanings and the exact diagnostic procedure can vary by vehicle make/model. Always consult OEM service information for precise definitions, sensor reference values, wiring diagrams, and timing procedures for the specific engine.
• The general approach described here covers CKP/CMP correlation issues common to many engines, but adjust steps as required by vehicle-specific layouts.

Summary

• P1335 is a powertrain code tied to crankshaft-camshaft position correlation. The typical culprits are CKP/CMP sensor faults or wiring issues, timing system problems, or PCM-related factors. A systematic approach - starting with data gathering and sensor electrical checks, followed by timing and mechanical inspection, then targeted component replacement - yields reliable diagnosis. Use OEM data for exact wiring and timing specs; the general diagnostic framework aligns with the OBD-II architecture described in Wikipedia's OBD-II sections (Diagnostic Trouble Codes and Powertrain Codes) and mirrors standard industry practice.

References drawn

• OBD-II Diagnostic Trouble Codes overview: explains that DTCs monitor parameters and trigger codes in modern vehicles (context for P-codes as a class of trouble codes).
• OBD-II Powertrain Codes overview: confirms P-codes fall under powertrain diagnostics and relate to engine/drive-train control systems.
• Additional context on OBD-II and emissions testing is provided to frame how codes relate to vehicle operation and testing contexts.

Note on data sources and probabilities

• The above probability estimates for causes are based on typical ASE field experience and common patterns observed in the industry, not on a published NHTSA data set with. If NHTSA or other complaint data becomes available for P1335, those percentages should be updated accordingly. When exact fault definitions or test methods vary by vehicle, always defer to OEM service information for accuracy.

This diagnostic guide was generated using verified reference data:

• Wikipedia Technical Articles: OBD-II

Content synthesized from these sources to provide accurate, real-world diagnostic guidance.

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