P0335 on a 2012 Ford F-150
Crankshaft Position Sensor Circuit Fault
What does P0335 mean on a 2012 Ford F-150?
P0335 is set when the engine control module does not receive a valid signal from the crankshaft position sensor. The crank sensor is the primary timing reference for the entire engine — fuel injection, ignition timing, and cam position correlation all depend on a clean crank signal. Without it, the engine will not start, or it will stall as soon as the signal drops out.
Symptoms on a 2012 Ford F-150
- Check Engine Light is illuminated
- Engine cranks but will not start
- Intermittent stalling that worsens with engine heat
- Hard starting after a long drive (heat-soak failure)
- Sudden stalling at highway speed with restart difficulty
- Tachometer reads zero or fluctuates while running
- Hard cold start with extended crank time
Likely causes on a 2012 Ford F-150
- Failed crankshaft position sensor (heat-related failure) Most commonEstimated repair: $100– $400
Heat-soak failure pattern is the textbook P0335 — fails when hot, recovers when cold.
- Damaged or melted sensor wiring near the exhaust CommonEstimated repair: $80– $350
- Corroded crank sensor connector CommonEstimated repair: $30– $200
- Damaged crank reluctor / tone ring (rare, requires teardown) RareEstimated repair: $1,500– $4,000
- Loose or improperly torqued sensor (cannot read gap correctly) OccasionalEstimated repair: $20– $100
- Failed PCM input (rare) RareEstimated repair: $400– $1,500
How to diagnose this on a 2012 Ford F-150
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Confirm the engine cranks but doesn't fire
P0335 typically presents as a crank-no-start. Confirm by cranking — the engine should rotate normally but never fire. If the engine fires intermittently, the sensor may be marginal; if it never fires, the sensor or wiring is fully out.
Tools: Common observation
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Locate the sensor on the engine
Crank sensors are typically mounted on the timing cover (front of engine), the bell housing (rear of engine), or on the side of the block. Consult the service manual. Most are accessible from underneath with a basic socket set.
Tools: Vehicle-specific service information
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Inspect wiring and connector
The sensor wiring routes close to the exhaust on many engines. Look for heat-damaged insulation, broken wires, or melted connectors. Sensor connectors near the firewall accumulate water and corrode — clean thoroughly.
Tools: Flashlight, Electrical contact cleaner
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Test sensor resistance and reference voltage
Most crank sensors are inductive (variable reluctance) with approximately 200–2,000 Ω resistance, or Hall-effect with a 5 V reference. Compare to the service manual. With the connector unplugged and key on, verify the 5 V reference reaches the connector (Hall-effect sensors).
Tools: Multimeter, Wiring diagram
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Heat-soak test for intermittent failures
P0335 that comes and goes with temperature is the textbook heat-soak failure pattern. Drive until the engine is hot, then attempt a restart immediately. If the engine cranks-no- starts hot and starts fine after cooling, the sensor is the cause even if cold-bench tests pass.
Tools: Patience
Common fixes
- Replace the crankshaft position sensor with an OEM part
- Repair damaged sensor wiring or connector
- Re-torque sensor to specification
- Replace damaged reluctor wheel (rare, major job)
About the 2010-2014 Ford F-150
The 2010-2014 Ford F-150 was commonly sold with the following powertrains: 3.5L EcoBoost V6, 5.0L V8, 2.7L EcoBoost V6. Common trims include XL, XLT, Lariat, King Ranch, Platinum.
The “crank-no-start” pattern that distinguishes P0335 from no fuel / no spark
Three different no-start patterns:
- No spark, no fuel pulse — crank sensor (P0335). The engine cranks normally but the ECM never commands injectors or coils because it has no timing reference.
- Fuel but no spark — ignition system. Coils or coil drivers.
- Spark but no fuel — fuel system. Pump, relay, or wiring.
A scan tool can confirm P0335 by reading the crank RPM PID during cranking — it should report the cranking RPM (typically 150–300 RPM). If it reports zero or doesn’t update, the crank signal is the problem.
Heat-soak failure: the most frustrating intermittent
A failing crank sensor often works perfectly cold and fails after the engine reaches operating temperature. The pattern owners describe: drive for 30+ minutes, stop somewhere (gas station, errand), and the car will not restart for 15-30 minutes — then starts fine. This is the crank sensor failing under heat. A new sensor is the only fix.
Replace the sensor preemptively if you see this pattern; the failure mode worsens until the vehicle will not start at all.
Why P0335 is more serious than P0340 (cam sensor)
The cam sensor is supplementary on most engines — the ECM can run on the crank signal alone in a “limp” mode. The crank sensor is not supplementary; without it the ECM has no idea where any piston is, when to fire, or even whether the engine is running. P0335 = engine off until fixed. P0340 = engine runs poorly but runs.