DF319

Code

RENAULT D

-> P0340 - Cam shaft sensor circuit

Brand: RENAULT

Type: D

Views: UK: 2 EN: 8 RU: 5

AI status

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Page language: EN

Causes

Faulty camshaft position sensor (damaged or failed)
Broken, corroded or disconnected connector or wiring (open, short to ground or battery, high resistance)
Loss of sensor reference or supply voltage (5V/12V) or poor ground
Damaged or missing reluctor/trigger wheel or timing belt/chain alignment problem
Intermittent wiring fault due to heat, vibration or pinched harness
ECM input circuit fault or software/calibration issue

Symptoms

Malfunction Indicator Lamp (MIL) illuminated / engine fault light on
Engine may crank but not start, or hard starting
Rough idle, misfires or reduced power
Stalling or intermittent loss of drive
Poor fuel economy or failed emissions test
Possible abnormal engine noise if timing jumped

What to check

Read and record freeze frame, live data and stored codes (confirm DF319 and any related codes such as crank/cam correlation)
Visually inspect sensor, connector and wiring for corrosion, damage, oil or water ingress
Check relevant fuses and power/ground at the sensor connector with ignition ON
Measure continuity and resistance of sensor wiring to the ECU (check for opens/shorts)
Use an oscilloscope or multimeter to observe cam sensor waveform while cranking/running
Check crankshaft position sensor and cam/crank correlation (mis-correlation can set cam sensor faults)

Signal parameters

Hall/logic (active) type: typical supply 5V (or 12V on some systems), output square wave 0 V to supply voltage (usually 0–5 V) synchronized to cam position
Magnetic/variable reluctor (VR) type: generates AC sine wave; amplitude increases with engine speed (0.2–4 V AC typical)
Pulse pattern: one or more pulses per camshaft revolution (cam sensor signals occur at half crankshaft speed for single pulse designs); frequency scales with engine RPM
Expected behavior: clean, repeatable waveform with correct timing relation to crank sensor; no intermittent dropouts or excessive noise

Diagnostic algorithm

Connect a diagnostic tool, read fault code DF319 and any related codes (P0340, P0335, cam/crank correlation codes). Record freeze-frame data.
Attempt a key-on and crank to reproduce the fault and monitor live cam sensor signal and correlated crank signal. Note missing or erratic pulses.
Visually inspect the cam sensor, connector, wiring harness and engine area for damage, oil/water ingress, loose pins or corrosion. Repair as needed.
With ignition ON, check sensor reference supply and ground at the connector (use backprobe). Confirm correct voltage (refer to vehicle manual; typically 5 V or 12 V supply for active sensors).
Measure sensor output while cranking and running: use an oscilloscope for best results. Observe waveform shape, amplitude, frequency and stability. For VR sensors use AC coupling.
Check continuity/resistance of wiring from sensor to ECM; perform wiggle test to detect intermittent faults. Repair broken wires, corrosion, or poor grounds.
Inspect camshaft reluctor/trigger ring and timing belt/chain alignment for missing teeth, damage, or jumped timing. Correct mechanical timing if required.
If wiring and timing are good but signal absent or irregular, replace camshaft position sensor with OEM or equivalent and retest.
If new sensor does not restore correct signal, test the ECM input circuit or swap with known-good ECM input (workshop level) or consult manufacturer tech data.
Clear codes and perform a test drive to confirm repair; re-scan and verify no recurrence.

Likely causes

Wiring connector corrosion or broken wires at the sensor harness
Failed camshaft position sensor
Faulty sensor supply or ground (fuse, splice or ECU connector)
Damaged reluctor/trigger wheel or timing chain/belt jumped tooth

Fault status

⚠️ Status

DF319 (P0340) — Camshaft position sensor circuit malfunction detected. Engine control module sees missing, weak, or out-of-spec cam signal; diagnostic required to locate sensor, wiring, timing or ECU fault.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours

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DF319 — -> P0340 - Cam shaft sensor circuit