HINO-P2049 serious Hino ›

DEF Injector - Disconnection (High Side)

The HINO-P2049 (Hino) diesel fault code means: DEF Injector - Disconnection (High Side). This is a serious severity code.

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Keep driving?
Short distances only
DIY difficulty
intermediate
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What Are the Symptoms of HINO-P2049?

  • Check Engine light
  • SCR malfunction lamp
  • DEF injection and NOx purification stopped
  • Output restricted after 500 miles and speed after 2,000 miles if it persists

What Causes HINO-P2049? (Most Likely First)

  • Open or short in the DEF injector harness High
  • Abnormal DEF injector resistance Medium
  • Failed DEF injector Medium

Can I Still Drive with HINO-P2049?

Short distances only. HINO-P2049 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What does P2049 mean on a Hino?

P2049 means DEF Injector - Disconnection (High Side). The DCU detects an open or short in the DEF injector circuit from its voltage: with the starter switch on and injector duty above 0%, the high-side circuit voltage is below 2 V for more than 0.05 seconds.

Is P2049 a Hino-specific code?

P2049 is an SAE-format powertrain code, but the title and the conditions here are Hino's own, read from Hino's service documentation, not a generic definition.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose HINO-P2049?

  1. Inspect the DEF injector harness for disconnection.

  2. Measure the injector resistance.

  3. Check the DTC detected by the DCU with the diagnostic tool.

Sources 2

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

  • Hino Workshop Manual, HINO 238 / 258LP / 268 / 338 series with J08E-VB and J08E-VC engines, DEF SCR System (DCU) chapter, DTC P2049 "DEF Injector - Disconnection (High Side)"technical description and detection conditions. Distributed through Hino's dealer service portal; no public link.
  • SAE J2012Diagnostic Trouble Code Definitions (defines P2049 as a generic OBD-II code)

P2049 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 P2049 Isuzu serious Reductant Injector Circuit High PACCAR serious Reductant Injector Circuit High

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