Diesel Trouble Codes

P0336 — Crankshaft Position Sensor A Circuit Range/Performance (5.9 Cummins Common Rail)

Diagnostic reference for 5.9L Cummins Common Rail (2003-2007) Dodge Ram 2500/3500 ISB.

Updated September 2, 2026

What it means

The ECM has detected the crankshaft position sensor signal is erratic, out of range, or inconsistent with expected engine operation. On this platform the engine is inline-6 with gear-driven timing, single crank sensor, single cam sensor.12

Most likely causes

  1. Crankshaft position sensor (CKP) signal erratic/out of range — Sensor internal fault, heat/vibration damage, or wiring/connector degradation causing intermittent or out-of-range signal. Typical on 5.9L Cummins Common Rail 2003-2007.1
  2. CKP wiring harness chafing, corrosion, or poor connection — Harness rub-through near engine block/harmonic balancer area, connector pin fretting or moisture intrusion leading to range/performance fault.1
  3. Reluctor/tone ring contamination or damage at crankshaft/harmonic balancer — Metal debris, oil/coolant contamination, or physical damage to the tone ring altering signal pattern; ECM sees range/performance inconsistency.1
  4. Power/ground supply issue to CKP circuit — Low/erratic reference voltage or ground affecting sensor output; ECM interprets as range/performance fault.1
  5. ECM signal processing anomaly — Internal ECM fault or software misinterpretation of otherwise valid CKP signal; less common but possible.1

How to diagnose

  1. Verify code P0336 is present and review freeze-frame for engine speed/load conditions at set.
  2. Inspect CKP sensor connector and wiring for chafing, oil contamination, corrosion, and secure seating; check harness routing near hot/exposed areas.
  3. Check CKP power and ground circuits for correct reference voltage and continuity to ECM per service information; look for intermittent opens.
  4. Inspect tone ring/reluctor at harmonic balancer for debris, damage, or misalignment; clean if contaminated.
  5. Monitor CKP signal with scan tool during cranking/running to confirm erratic or out-of-range pattern vs. expected RPM.
  6. If signal is stable, compare camshaft position sensor correlation; single cam sensor on gear-driven timing.
  7. Clear codes and test drive to confirm repeatability; note conditions that trigger P0336.

Parts and tools you may need

Rough cost and difficulty

Parts and labor vary by region and shop. CKP sensor replacement is common; wiring repair cost depends on extent of harness damage. Obtain quotes before proceeding.

When to see a pro

If diagnosis points to internal ECM fault, tone ring replacement requiring harmonic balancer removal, or persistent intermittent signal with no obvious wiring fault, have a qualified diesel technician evaluate. Do not attempt high-pressure fuel or brake system work as part of this diagnosis.

Sources

  1. Curated DTC seed — 5.9 Cummins Common Rail (curated) ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎

  2. Curated DTC seed — 5.9 Cummins Common Rail (curated) ↩︎