What this code means
P0335 may indicate the PCM is not receiving a clean crankshaft position signal or is seeing a crank signal that becomes erratic.
What the vehicle may do
- The engine may crank and not start.
- The engine may have intermittent starting or stalling symptoms.
- The engine may run poorly if the crank signal drops out or becomes unstable.
Possible fault areas
- Possible CKP sensor circuit concern.
- Possible CKP sensor concern.
- Possible crankshaft pulse wheel concern.
- Possible PCM-side concern.
Diagnostic path
Opening context
On this 2015 to 2025 F-150 with the 5.0L Coyote, P0335 means the PCM may not be seeing a clean, believable crankshaft position signal. The truck may crank and not start, may have an intermittent start or stall, or may run with a crank signal that drops out or gets erratic. Broadly, think CKP sensor circuit, sensor condition, crank pulse wheel condition, or, less often, a PCM-side concern. If other crank, cam sync, or profile learn codes are present, check what they mean first, but for P0335 we are going to stay focused on the crankshaft position signal path.
Start with the RPM signal while cranking
Start with the basic system checks, then follow a structured diagnostic approach. Before you trust the crank RPM reading, make sure the battery is fully charged and the starting system is working correctly. Normal engine cranking speed is between 150 RPM and 350 RPM, and the engine should crank for greater than 3 seconds while attempting to start. A value of 0 revolutions per minute, RPM, indicates a CKP concern; said another way, 0 RPM while cranking is a red flag for the crank signal. Remove the fuel pump fuse to disable the fuel pump. Turn the ignition ON, access the PCM data, monitor the RPM PID, and crank the engine. The first decision is whether RPM is greater than 150. If RPM is greater than 150 and P0335 is the code you are chasing, move to the physical CKP sensor and trigger wheel check. If RPM is not greater than 150, continue into that same physical inspection path. If the engine cranks less than 3 seconds with no RPM signal, do not jump ahead. Verify base engine timing, make sure the camshaft sensor trigger wheels are not damaged, and confirm the camshafts are rotating while cranking before continuing.
Check the CKP sensor and trigger wheel
Next, turn the ignition OFF and inspect the CKP sensor and trigger wheel. Look for contamination or debris on the trigger wheel, and look for obvious physical damage at the sensor and wheel. A trigger wheel that is physically damaged, bent more than 1.0 mm, or contaminated on the magnetic surfaces can cause an intermittent CKP signal. If you find a real concern here, repair as necessary, reset keep alive memory, KAM, and run the neutral profile correction with the scan tool. If the sensor and wheel look good, be careful about the next branch and stay with the path your test result puts you on.
Bias voltage and two-wire CKP circuit checks
The next block covers CKP bias voltage, sensor resistance, shield ground, and circuit integrity checks. If your diagnostic path puts you into these checks, pause and make sure you have the exact connector and terminal callouts before measuring. Do not guess at terminals. The test logic is still useful: with the CKP sensor disconnected and ignition ON, correct PCM CKP bias voltage is between 1 V - 3 V. If that is correct, turn the ignition OFF and check CKP sensor resistance; the expected range is between 250 Ω - 1100 Ω. If it is not in that range, install a new Crankshaft Position sensor, reset KAM, and run the neutral profile correction with the scan tool. The shield ground check is also part of this block. The CKP harness shield surrounds the CKP circuits to protect the signal from electrical noise, and it is grounded internally through the PCM. With the PCM disconnected, resistance between the CKP shield in the harness and the PCM connector terminal should be less than 5 ohms. If it is not, repair the open circuit or intermittent ground connection, clear the PCM DTCs, and repeat the self-test. Then check for a short between CKP positive and CKP negative; resistance should be greater than 10000 Ω. Check the CKP circuits for an open; resistance should be less than 5 Ω. Check for a short to ground; resistance should be greater than 10000 Ω. Finally, with ignition ON, check for a short to voltage. If any voltage is present where it should not be, repair the short circuit, clear the PCM DTCs, and repeat the self-test. If no voltage is present at that point, move on to the intermittent inspection.
5.0L connector-specific sensor voltage and signal circuit checks
If the physical CKP sensor and trigger wheel inspection did not show a concern, go to the 5.0L connector-specific checks. Turn the ignition OFF, disconnect the CKP sensor connector, then turn the ignition ON. Measure voltage between C1339 Pin 3 and C1339 Pin 1. The expected value is between 4.5 V - 5.5 V. If that voltage is correct, turn the ignition OFF, disconnect the PCM connector, and check the signal circuit for an open. Measure resistance between C1339 Pin 2 and C175E Pin 98. It should be less than 5 Ω. If it is not, repair the open circuit, clear the PCM DTCs, and repeat the self-test. If the open check passes, check for shorts between circuits. Measure resistance between C1339 Pin 2 and C1339 Pin 1, and between C1339 Pin 2 and C1339 Pin 3. Resistance should be greater than 10000 Ω. If it is not, repair the short circuit, clear the PCM DTCs, and repeat the self-test. Then turn the ignition ON and check for a short to voltage at C1339 Pin 2. If any voltage is present, repair the short circuit, clear the PCM DTCs, and repeat the self-test. If no voltage is present, move to the intermittent harness inspection.
Intermittent harness inspection
For an intermittent P0335 path, turn the ignition OFF, connect the PCM connector, and visually inspect the CKP and CMP harness areas. Look for chafed wires or other physical damage that could create an intermittent short in the CKP or CMP circuits. If you find a concern, repair as necessary, clear the PCM DTCs, and repeat the self-test. If you do not find a concern, continue to the connector seating and corrosion check.
Connector condition and final diagnostic decision
Now verify connector condition and correct operation. Turn the ignition OFF, disconnect the PCM connector, and disconnect the CKP sensor connector. Visually inspect for pushed out pins and corrosion. Then connect all PCM connectors and the CKP sensor connector, and make sure the connectors are fully seated. After that, verify whether the concern is still present. If the concern is still present and the symptom is cranks no start, move into the appropriate no-start testing rather than guessing. If the concern is still present for the remaining P0335 path, install a new Crankshaft Position sensor, reset KAM, and run the neutral profile correction with the scan tool. If the concern is no longer present, the system is operating correctly at this time, and the concern may have been caused by a loose or corroded connector.
Verify the repair and close
Keep verification separate from testing. After any circuit repair, clear the PCM DTCs and repeat the self-test. Where KAM reset and neutral profile correction are called for, do those steps with the scan tool before making the final call. The takeaway is simple: prove the crank RPM signal first, inspect the wheel and sensor, then work the circuit checks in order so you do not turn an intermittent CKP signal into a parts guess. For more diagnostic training, visit stepdiagnostics.com.
Final check
P0335 is often best handled by confirming crank RPM data first, then checking the sensor, wheel, wiring, and connector condition before making a repair decision.
For more guided automotive diagnostics, visit STEP Diagnostics.
