NOx Sensor A / B Correlation
The HINO-P220B (Hino) diesel fault code means: NOx Sensor A / B Correlation. This is a moderate severity code.
Unverified. We could not confirm this code's definition against freely available manufacturer documentation, so treat the meaning, severity and fix guidance on this page as unconfirmed. Check it against the manufacturer's service information for your exact model and serial range before acting on it. This page is kept out of search engines for that reason, and we are working through this family manual by manual.
- Keep driving?
- Short distances only
- DIY difficulty
- intermediate
- Estimated cost
- $500-$2,800
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View pilot availability →What Are the Symptoms of HINO-P220B?
- DEF warning + progressive derate to 5 mph
- No-restart inducement when derate timer expires
- Frequent DEF refills / high consumption
- Crystalline deposits around DEF doser
- High NOx in live data
What Causes HINO-P220B? (Most Likely First)
- Failed NOx inlet or outlet sensor (Hino NOx service life 150K-250K mi) Very Likely
- Crystallized DEF at doser from short trips / no-heat soak Likely
- DEF pump module motor failure Possible
- Contaminated or aged DEF (past 12-24 mo) Possible
- Exhaust leak upstream of SCR creating false NOx ratio Possible
Can I Still Drive with HINO-P220B?
Short distances only. HINO-P220B is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does Hino code P220B mean?
Hino diagnostic trouble code P220B (NOx Sensor A / B Correlation) is a moderate-severity fault on Hino medium-duty diesel engines. It indicates a problem in the SCR / DEF system that should be verified with a scan tool (Hino DX3 / DX4) before replacing any parts.
Can I drive my Hino truck with P220B?
Short runs may be possible but do not ignore — Hino medium-duty aftertreatment faults cascade quickly into 5-mph derate or no-restart. Schedule diagnosis immediately.
How much does it cost to fix Hino P220B?
Estimated repair cost runs $500-$2,800. Sensor, wiring, and DEF-related repairs fall at the low end; DPF service, turbo, injector, and EGR cooler work fall at the high end and may require dealer-level programming.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose HINO-P220B?
Confirm P220B on Hino DX3 or DX4. Capture NOx inlet / outlet live, DEF dosing state, and reductant pressure.
Refractometer-test DEF; must be 32.5% urea ± 1%. Below 30% = replace fluid.
Command DEF pump pressure build. Target pressure must be reached within spec time; inspect pump seals and motor if not.
Inspect DEF doser tip for white crystalline build-up. Remove, soak in warm distilled water, blow out, reinstall.
If NOx sensor live data shows sluggish response or stuck values, replace sensor(s) — often both fail together.
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J1939-73Application Layer: Diagnostics (defines the SPN/FMI fault-identifier framework)
- SAE J2012Diagnostic Trouble Code Definitions (defines P220B as a generic OBD-II code)
P220B on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
Which Vehicles Commonly Get HINO-P220B?
- Hino 155 / 155h with J05 5.1L
- Hino 195 / 195h (hybrid) with J05D 5.1L
- Hino 258 / 258LP / 268 with J08 7.7L
- Hino 338 / 338CT with J08 7.7L
- Hino 358 / 358CT (post-2019 J-series / A09C)
- Toyota Dyna / Hino-branded export chassis with J05/J08
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