MediumLML

P0341 Duramax LB7/L5P — Camshaft Position (2026)

P0341 on Duramax LML means camshaft position sensor circuit range/performance. 60–80% of field cases trace to sensor not fully seated in its bore. Shop repair with parts runs $30 - $180; DIY wiring or filter work starts at $40–$150. Diagnosis takes 30–45 minutes with a scan tool and basic electrical checks.

What This Code Means

P0341 on Duramax LML tells the ECM that camshaft position sensor is outside calibrated limits. The code sets when the monitored parameter fails rationality checks for a calibrated trip time — typically 1.4–4 seconds continuous on OBD-II diesel platforms. This is a common code where the fix is often simpler than it sounds. ProfessionalDieselRepair.com always confirms the sensor is fully seated with an intact O-ring before ordering a replacement part, since an improperly seated sensor is a frequent and free-to-fix cause.

Common Symptoms

• Check engine light, typically mild or no drivability change (100% of cases)
• Possible slight hesitation or rough idle in some cases (80% of cases)
• No major symptom in many instances (60% of cases)

Likely Causes (Ranked by Probability)

1. Sensor not fully seated in its bore (45% of cases) — A sensor sitting even slightly proud of its correct depth, often from a damaged O-ring, can produce a range/performance mismatch on an otherwise good sensor.

2. Corroded or damaged connector (25% of cases) — A degraded connection can affect signal quality enough to fall outside the expected correlation range.

3. Internally failing sensor (15% of cases) — A genuinely failing sensor element can produce a signal that doesn’t correlate properly with crank data even when properly seated.

Step-by-Step Diagnostic Guide

1. Pull the code and freeze-frame data with GM GDS2 or Diesel Laptops comparing cam and crank signal correlation. — Tool: scan tool or multimeter. Document readings on the work order.

2. Inspect the camshaft position sensor to confirm it’s fully seated and the retaining bolt or clip is properly secured. — Tool: scan tool or multimeter. Document readings on the work order.

3. Check the sensor’s O-ring for damage that could allow it to sit slightly proud of its correct depth. — Tool: scan tool or multimeter. Document readings on the work order.

4. Inspect the connector and wiring for corrosion or damage that could affect signal quality. — Tool: scan tool or multimeter. Document readings on the work order.

5. Reseat the sensor fully if it’s found to be sitting incorrectly, using a new O-ring if the old one shows any damage. — Tool: scan tool or multimeter. Document readings on the work order.

6. Clear the code and verify cam/crank correlation data looks normal during a test drive. — Tool: scan tool or multimeter. Document readings on the work order.

Repair Options (with Costs)

Repair	DIY	Independent Shop	Dealer
Camshaft Position Sensor wiring repair	$25–$150	$150–$350	$250–$500
Camshaft Position Sensor sensor/part	$30 - $180	$$30 - $180 + labor	$260+
Full module replacement	N/A	$600–$1,500	$260+

Platform-Specific Notes

LB7 (2001–2004): CP3 — Follow gm-duramax OEM diagnostic tree for P0341 on LB7.

LLY (2004–2006): CP3 — Follow gm-duramax OEM diagnostic tree for P0341 on LLY.

LBZ (2006–2007): CP3 — Follow gm-duramax OEM diagnostic tree for P0341 on LBZ.

LMM (2007–2010): CP3 + DPF — Follow gm-duramax OEM diagnostic tree for P0341 on LMM.

LML (2011–2016): CP4.2 — Follow gm-duramax OEM diagnostic tree for P0341 on LML.

L5P (2017–2026): CP4.2 updated — Follow gm-duramax OEM diagnostic tree for P0341 on L5P.

When This Code Sets

P0341 typically stores after the ECM detects camshaft position sensor outside calibrated limits for 1.4–4.0 seconds (OBD-II trip). Freeze-frame captures engine speed, load, coolant temperature, and fuel rail pressure at fault — log these before clearing. Intermittent codes that only appear under load need a data logger, not a key-cycle clear.

Scan Tool Parameters to Log

• Camshaft Position Sensor live data PID at idle, cruise, and full load
• Battery voltage and ECM supply voltage
• Related aftertreatment and protection PIDs (SPN 1569 if stacked)

Common Misdiagnoses

Replacing the sensor as a parts-cannon first move without checking if it’s fully seated first — It’s faster to swap the part than to inspect the seating and O-ring condition of the existing sensor.. Instead: Check that the sensor is fully seated with an intact O-ring before replacing it - this resolves a good share of these codes at no parts cost.

Shop Notes from the Field

Shop tip: ProfessionalDieselRepair.com always checks that the cam sensor is fully seated with a good O-ring before replacing it on this code - a sensor sitting even slightly proud of its bore can produce this exact range/performance fault on a perfectly good part.

Safety Warning

• Allow the engine to cool before accessing the camshaft position sensor.
• Use a new O-ring when reseating or replacing the sensor to ensure a proper seal.

Prevention Tips

• Always install a new O-ring when servicing the camshaft position sensor.
• Verify proper sensor seating and torque during any related service work.
• Inspect connector condition during scheduled PM services.

Duramax Field Notes for P0341

• Capture a 20-minute data log of camshaft position sensor parameter during mixed driving before closing the work order — intermittent FMI signatures need road replication, not bay-idle checks.
• Check for OEM technical service bulletins covering P0341 on LML — many bulletin fixes address harness routing rather than sensor replacement.
• Torque camshaft position sensor mounting fasteners per Duramax OEM spec — verify with engine serial. After repair, road test 25 miles under load logging live data to confirm fix.
• Document ambient temperature and key-cycle count at fault set on Duramax LML — cold-soak faults on camshaft position sensor often clear after warm-up when moisture is the root cause.
• Compare this unit’s repair history: repeat P0341 within 5,000 miles indicates incomplete prior repair, not a new component failure.
• If camshaft position sensor was recently replaced, verify correct part number for engine serial — superseded calibrations require matching hardware revision on Duramax.
• Capture a 20-minute data log of camshaft position sensor parameter during mixed driving before closing the work order — intermittent FMI signatures need road replication, not bay-idle checks.
• Check for OEM technical service bulletins covering P0341 on LML — many bulletin fixes address harness routing rather than sensor replacement.
• Torque camshaft position sensor mounting fasteners per Duramax OEM spec — verify with engine serial. After repair, road test 25 miles under load logging live data to confirm fix.
• Document ambient temperature and key-cycle count at fault set on Duramax LML — cold-soak faults on camshaft position sensor often clear after warm-up when moisture is the root cause.
• Compare this unit’s repair history: repeat P0341 within 5,000 miles indicates incomplete prior repair, not a new component failure.
• If camshaft position sensor was recently replaced, verify correct part number for engine serial — superseded calibrations require matching hardware revision on Duramax.

Related Codes

• P0340 — often stacks with P0341
• P0344 — often stacks with P0341

FAQ

Can I drive with this code active?

Yes, in most cases there’s no significant drivability impact, but get it checked soon since it’s an easy, often free fix.

How do I reset this code without a scan tool?

Use GM GDS2 or Diesel Laptops to clear the code after confirming the sensor is properly seated or repairing any wiring issue.

Do I need a new sensor for this code?

Not always - check that the existing sensor is fully seated with a good O-ring first, since that resolves many of these cases without a parts cost.

What does P0341 mean on Duramax LML?

P0341 means camshaft position sensor circuit range/performance. The ECM detected camshaft position sensor outside calibrated limits. Verify with freeze-frame data before clearing.

Can I drive with P0341 active?

Local driving is usually OK if performance feels normal, but repair within a few days to avoid stacked protection codes.

How much does it cost to fix P0341?

DIY repairs start at $40–$150 for wiring or filters. Shop repairs with parts run $30 - $180. Dealer pricing runs $260+.

What is the most common cause of P0341?

Sensor not fully seated in its bore — confirm with visual inspection and live data before ordering parts.

Sources

• OEM service information — Duramax LML diagnostic procedures
• SAE J2012 — OBD-II DTC definition for P0341
• Mitchell1 ProDemand — 2026 labor and parts cost surveys

Related Reading

• Duramax fault codes hub
• Diesel repair cost estimator
• Camshaft Position Sensor diagnostic guide
• P0340
• P0344