POWERSTROKE-P0502 moderate Power Stroke ›

VSS Circuit Low Input

The POWERSTROKE-P0502 (Power Stroke) diesel fault code means: VSS Circuit Low Input. This is a moderate severity code.

My Garage →
Keep driving?
Yes, but fix soon
DIY difficulty
beginner
Estimated cost
$40-$200
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What Are the Symptoms of POWERSTROKE-P0502?

  • Speedometer drops out
  • Harsh shifts
  • CEL

What Causes POWERSTROKE-P0502? (Most Likely First)

  • Failed VSS sensor on trans tailshaft Likely
  • Damaged VSS wiring Likely

Can I Still Drive with POWERSTROKE-P0502?

Yes, but fix soon. POWERSTROKE-P0502 is rated moderate severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring it.

Frequently Asked Questions

What is P0502 on a 7.3L Power Stroke?

P0502 on a 7.3L Power Stroke (1994-2003) indicates: VSS Circuit Low Input. This is a known diagnostic trouble code on this engine family and typically points to the causes listed above.

Can I drive with P0502 on my Power Stroke?

Yes, you can generally drive with this code, but diagnose it soon to prevent further damage.

How much does it cost to fix P0502?

Repair cost is typically $40-$200 depending on the underlying cause and whether you DIY or use a shop. Diagnostic time alone runs $100-$180 at most independent diesel shops.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose POWERSTROKE-P0502?

  1. Scan VSS PID during driving.

  2. Replace sensor.

Sources 1

This page is built from documented references. Verify against your own service info before repair work.

  • SAE J2012Diagnostic Trouble Code Definitions (defines P0502 as a generic OBD-II code)

P0502 on Other Platforms

The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:

Gas / Automotive (OBD-II) Generic OBD-II definition for P0502

Which Vehicles Commonly Get POWERSTROKE-P0502?

  • 1994.5-1997 Ford F-250/F-350 7.3L Power Stroke
  • 1999-2003 Ford F-250/F-350 Super Duty 7.3L Power Stroke
  • 1999-2003 Ford F-450/F-550 Super Duty 7.3L Power Stroke
  • 1994.5-2003 Ford E-350/E-450 7.3L Power Stroke
  • 2000-2003 Ford Excursion 7.3L Power Stroke

Explore More

More Power Stroke codes → Diesel home All diesel codes Heavy-duty Guides

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