Accelerator Pedal Sensor 2 Performance
The MAXXFORCE-P1538 (MaxxForce) diesel fault code means: Accelerator Pedal Sensor 2 Performance. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- intermediate
- Estimated cost
- $250-$900
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Common Symptoms
- Derate on throttle tip-in
- CEL
Probable Causes (Ranked by Likelihood)
- Failed APP sensor Likely
Frequently Asked Questions
What is P1538 on a MaxxForce DT (7.6L)?
P1538 on a MaxxForce DT (7.6L) (2007-2015) indicates: Accelerator Pedal Sensor 2 Performance. This is a known fault code on the MaxxForce engine family and typically points to the causes listed above.
Can I drive with P1538 on my MaxxForce?
Only drive short distances to reach a repair facility. Continued operation may cause further damage or progressive derate.
How much does it cost to fix MaxxForce P1538?
Repair cost is typically $250-$900 depending on the underlying cause and shop rate. Many MaxxForce faults (especially EGR cooler, head bolt, and VGT repairs) are major expenses that drove fleet owners to repower with Cummins or retire these trucks early.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
Replace accelerator pedal assembly.
Some APP sensors require relearn via service tool.
P1538 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
Commonly Affected Vehicles
- International 4300 DuraStar MaxxForce DT
- International 4400 DuraStar MaxxForce DT
- International 7300/7400/7500 WorkStar MaxxForce DT
- IC Bus CE-Series MaxxForce DT
- IC Bus RE-Series MaxxForce DT
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