YANMAR-P1260 serious Yanmar ›

Yanmar Immobilizer / Anti-Theft Active

The YANMAR-P1260 (Yanmar) diesel fault code means: Yanmar Immobilizer / Anti-Theft Active. This is a serious severity code.

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Keep driving?
No -- stop driving
DIY difficulty
intermediate
Estimated cost
$50-$400
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Common Symptoms

  • Will not crank on compact tractor
  • Key indicator lamp flashing

Probable Causes (Ranked by Likelihood)

  • Wrong key / key chip not paired Likely
  • Immobilizer antenna failure around ignition switch Possible

Step-by-Step Diagnostic Procedure

  1. Re-learn key in SmartAssist.

  2. Check antenna ring continuity.

Frequently Asked Questions

What is Yanmar code P1260?

Yanmar P1260: Yanmar Immobilizer / Anti-Theft Active.

Can I keep operating with Yanmar code P1260?

Do not operate. Risk of engine damage.

How much does Yanmar P1260 cost to fix?

Typical cost: $50-$400. Yanmar SmartAssist / YDT diagnostic software is often required.

P1260 on Other Platforms

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

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