P0339 on Jeep: How to Diagnose & Fix
Crankshaft Position Sensor A Circuit Intermittent
3 Jeep models · 3 documented issues · 3 critical · $60-$450 repair
P0339 on Jeep by model: symptoms, diagnosis and fix
The crankshaft position sensor (CKP) on the 4.7L (and 4.0L) Grand Cherokee commonly fails from heat-soak: it works when cold but its internal resistance rises when hot, so the PCM loses the crank signal and the engine won't restart until it cools 30-60 minutes, or it stalls randomly while driving. A cranks-but-no-start after a hot soak is the classic signature and a top WJ search.
Common Symptoms
- Cranks but will not start when hot; restarts after cooling down
- Random stalling while driving with immediate/eventual restart
- Intermittent no-crank-signal
- Tachometer drops to zero while stalling
How to Fix
Verify with a scan tool (loss of CKP signal / no RPM during crank) rather than parts-swapping. Replace with a quality sensor — Mopar crankshaft position sensor 56028666AB fits 1999-2004 4.7L (56028133-series is the CAMSHAFT sensor, do not confuse). Use OEM Mopar or premium NGK/NTK; cheap sensors frequently fail again. On some 4.7L applications the starter must be removed for access.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Mopar crankshaft-position sensorOEMMopar 56028666AB
Replacement after testing confirms the CKP sensor itself failed on a 1999-2004 Grand Cherokee 4.7L Fitment/availability: 56028666AB is the exact reviewed genuine sensor and supersedes 56028666AA, 56028136AC/AD and 56028137AC. Confirm VIN…
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Owner tips & cautions
- WarningDo not replace the sensor from P0320 alone. The factory tree also lists CKP supply, ground, signal wiring, cam signal, and PCM causes.
- WarningRecall 04V-112 is a limited 2004 4.0L campaign; it does not make a 1999-2004 4.7L sensor replacement a recall repair.
- TipThe 4.7L sensor sits above the starter. Follow the factory O-ring, flush-seating, and torque precautions so the new sensor is not damaged during installation.
Sources for this issue (3)
On the 2.4L World Engine the crankshaft position sensor sits at the rear of the block and its harness is routed close to the exhaust manifold, where heat embrittles the insulation and the connector terminals. The result is an engine that stalls at idle or while driving, restarts after cooling, and sets P0339 - an intermittent-circuit code rather than a hard failure, which is why parts-cannon repairs miss it. For 2016 vehicles specifically, FCA issued campaign S89 / NHTSA 16V907000 for improperly manufactured crankshaft and camshaft sensor connector terminals that create the same intermittent connection and stall.
Common Symptoms
- Engine stalls at idle or while driving
- Restarts only after sitting and cooling
- Cranks but will not start when hot
- Check engine light
- Tachometer drops to zero momentarily
How to Fix
If the vehicle is a 2016, check the VIN for 16V907000 - the dealer replaces the affected sensor connector terminals free. Outside that population, replace the sensor with a Mopar or OE-supplier part (cheap aftermarket sensors are a documented repeat-failure source), and inspect and re-loom the harness away from the manifold with high-temp sleeving, repairing any melted connector. The sensor itself is inexpensive but access behind the heat shield at the rear of the block drives labor; expect $200-$450 at a shop.
Sources for this issue (2)
The crankshaft position sensor (CPS) on the 4.0L (and 2.5L) inline engines mounts on the transmission bellhousing and is exposed to severe heat soak. As it ages it develops intermittent thermal failure: the engine stalls without warning once hot, then refuses to restart until it cools, after which it runs fine again — a maddening, hard-to-replicate fault. Frequently the CPS fails with NO check-engine light and NO stored code, so it is commonly misdiagnosed. It is a top-searched TJ/early-Wrangler stalling complaint and a roadside-safety concern because the stall is sudden.
Common Symptoms
- Engine stalls suddenly while driving, especially when hot
- Will not restart until the engine cools, then runs normally
- Cranks but no start when hot
- Often no check-engine light and no stored DTC
- Intermittent stumble/backfire
- Hard starting in rainy/humid weather
How to Fix
When the engine stalls hot and won't restart, unplugging and reconnecting the CPS connector (near the back of the intake) often resets the PCM and the engine fires — a strong indicator the CPS is failing. Replace the crankshaft position sensor with a Mopar or NTK/NGK unit (Mopar 56027866AE for many 4.0L applications; 4727451AA covers 2003-2011 TJ/JK 3.8L & 4.0L). Avoid bargain aftermarket sensors — out-of-tolerance units cause repeat no-starts. No relearn required; verify with a hot road test.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Crown 56027865AB crankshaft-position sensorOEMCrown 56027865AB
Manual-transmission/early-engine sensor replacement after hot testing confirms signal dropout Fitment/availability: 1997-2004 Wrangler TJ 4.0L manual-transmission branch; the underlying application family also covers specified 1997-2002 …
- Crown 4897321AA crankshaft-position sensorOEMCrown 4897321AA
Early automatic-transmission sensor replacement after hot testing confirms signal dropout Fitment/availability: 1997-2002 Wrangler TJ 4.0L automatic-transmission branch. Confirm connector and transmission; not the manual or 2003-2006 bra…
- Standard Motor Products PC243 crankshaft-position sensorOEMStandard PC243 / Mopar cross 4727451AA
Later TJ 4.0L sensor replacement after hot testing confirms crank-signal dropout Fitment/availability: Crosses Mopar 4727451AA for specified 2003-2006 Wrangler TJ 4.0L applications; verify transmission/connector and exact catalog fit bef…
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Sources for this issue (2)
P0339 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0339 mean on a Jeep?
P0339 stands for "Crankshaft Position Sensor A Circuit Intermittent." The crankshaft position (CKP) sensor 'A' signal is intermittent, dropping in and out. The controller intermittently loses the crank reference, typically causing random stalls or no-restart events that are hard to reproduce. Often a loose connector, marginal sensor, or chafed wire. On Jeep it is documented across 3 models: Grand Cherokee, Patriot, Wrangler.
What are the most common causes of P0339?
The most common causes of P0339 are: Intermittent wiring or loose/corroded connector, Heat-sensitive or marginal CKP sensor, Variable air gap from a loose sensor, Damaged/chafed harness, Reluctor ring runout. The specific cause varies by vehicle.
How much does it cost to fix P0339 on a Jeep?
Published repair estimates on Jeep range from $60 to $450 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0339 on a different make?
View P0339 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.