HINO-P0403 moderate Hino ›

Exhaust Gas Recirculation Control Circuit

The HINO-P0403 (Hino) diesel fault code means: Exhaust Gas Recirculation Control Circuit. This is a moderate severity code.

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Keep driving?
Short distances only
DIY difficulty
intermediate
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What Are the Symptoms of HINO-P0403?

  • Check Engine light
  • EGR not operating, possible reduced power

What Causes HINO-P0403? (Most Likely First)

  • Open or shorted wire in the EGR control circuit High
  • Failed EGR valve actuator High
  • Damaged or corroded connector at the valve Medium

Can I Still Drive with HINO-P0403?

Short distances only. HINO-P0403 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What does P0403 mean on a Hino?

P0403 means Exhaust Gas Recirculation Control Circuit. The control module detected an electrical fault in the EGR valve control circuit.

Is P0403 a Hino-specific code?

No. P0403 is a generic OBD-II code defined by SAE J2012, so it means the same thing on any vehicle that sets it. The exact conditions Hino uses to set it on its diesels are in Hino service information.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose HINO-P0403?

  1. Check the actuator resistance against the specification.

  2. Inspect the connector and harness to the EGR valve.

  3. Check the control circuit for opens and shorts back to the module.

Sources 3

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

P0403 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 P0403 Isuzu moderate Exhaust Gas Recirculation Control Circuit Kubota serious EGR Control Circuit Yanmar serious EGR Control Circuit Malfunction

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