4AA-B45W
Nissan Dayz B45W specs
B45W is the model code of the Nissan Dayz, a kei car. Japan’s transport ministry lists it in its fuel economy lists from 2020–2026 under the model type 4AA-B45W. A genuine car’s chassis number starts B45W-.
B45W at a glance
- Make
- Nissan
- Model
- Dayz
- Model code
- B45W
- Model types
- 4AA-B45W
- In MLIT’s lists
- 2020–2026
- Engines
- BR06-SM21 659 cc petrol
- Gearboxes
- CVT automatic
- Drive
- front-wheel drive
- Kerb weight
- 860–880 kg
- Official fuel economy
- 19.2–25.2 km/L (54–71 mpg)
Fuel economy is from Japan’s official tests and is usually better than you’ll see on UK roads. MLIT doesn’t list power or torque.
4AA-B45W
Listed 2020–2026. The 4AA prefix (our explanation, not MLIT’s) means hybrid passenger car certified to Japan’s 2018 emissions rules, 25% below their limits. Check 4AA-B45W against ULEZ and clean air zones.
| Engine | Gearbox | Drive | Weight | Seats | Fuel economy | Listed |
|---|---|---|---|---|---|---|
| BR06-SM21659 cc petrol | CVT automatic | front-wheel drive | 860–880 kg | 4 | 24.8–25.2 km/L70–71 mpg, Japanese JC08 test | 2020–2026 |
| BR06-SM21659 cc petrol | CVT automatic | front-wheel drive | 860–880 kg | 4 | 19.2–21.5 km/L54–61 mpg, WLTC test | 2020–2026 |
Each row is one version as MLIT lists it. A version can appear twice when MLIT gave figures on two tests that year. Low-emission stars and trim names aren’t shown. MLIT gives fuel economy in km/L; the mpg figures are our conversion to UK gallons. Japanese tests are gentler than real UK driving, so expect less.
B45W build year by chassis number
Japan’s carmakers list the chassis numbers each code was built with every year from 2015. Find the serial below, or use the build year finder.
| Built | Chassis numbers |
|---|---|
| 2019 | B45W-000001 to 014451 |
| 2020 | B45W-014452 to 019617B45W-100001 to 103960 |
| 2021 | B45W-103961 to 107870 |
| 2022 | B45W-107871 to 110337B45W-300001 to 301033 |
| 2023 | B45W-301034 to 302730B45W-400001 to 402546 |
| 2024 | B45W-402547 to 404487B45W-500001 to 502102 |
| 2025 | B45W-502103 to 504141B45W-600001 to 602008 |
From the JAMA chassis number lists: 車台番号一覧表. We keep only the chassis code, serial ranges and year. JAMA calls them reference information, not a certificate.
Check a B45W before you buy
Make sure the car is what the advert says: the chassis number on the V5C should start B45W-, and the engine and gearbox should match one of the versions above. Our free check reads the UK MOT history and compares it with the chassis code.
Other Nissan Dayz model codes
Questions
What engine does the B45W have?
MLIT lists the Nissan Dayz B45W with BR06-SM21 659 cc petrol.
What fuel economy does the B45W get?
Officially between 19.2 and 25.2 km/L (about 54–71 mpg), depending on the version, on Japan’s own tests. Real-world figures are usually lower, especially against the older 10-15 mode test.
How heavy is the B45W?
Between 860 and 880 kg kerb weight, depending on the version.
Is 4AA-B45W the same as B45W?
Yes. 4AA-B45W is the full model type: the letters before the hyphen are Japan’s emissions code, which changed as the rules were tightened, and B45W is the model code. The chassis number starts with B45W-.
About these figures
The model types, engine codes, capacities, gearboxes, drive, weights, seats and km/L figures are copied from MLIT’s yearly lists of cars on sale in Japan each March, so “listed” years are list years, not exact production dates. The English model names, mpg conversions, emissions code explanations and chassis number matching are ours. Lists before 2013 were printed as PDFs that we read by machine; where an older list gives an engine code that doesn’t match its capacity, we’ve used the figure the same model type has in other years. Check anything that matters against the car’s own papers. Spotted a mistake? Email [email protected]. All Nissan model codes.
Source: Ministry of Land, Infrastructure, Transport and Tourism (MLIT), Japan, fuel economy lists 2004–2026, used under the Public Data License 1.0. Edited and translated by JDM History.