What Honda B12 includes
- Replace engine oil and filter (the B): The core of every B service. Honda specifies 0W-20 full synthetic on most modern models; the oil life algorithm decided it is done.
- Full inspection (also the B): Brakes front and rear, suspension, steering ends, fluid levels, driveshaft boots, fuel lines and exhaust. This is where a shop earns its labor - a torn CV boot caught here is a cheap fix instead of a joint replacement.
- Rotate tires (the 1): Front tires wear faster on a front-wheel-drive Honda. Rotation evens the wear so the set ages together.
- Replace engine air filter (the 2): A restricted filter costs fuel economy before it costs power. Minutes to swap on most Civics, Accords and CR-Vs.
- Replace dust and pollen (cabin) filter (also the 2): Behind the glove box on most models. If airflow from the vents has felt weak, this is usually why.
- Inspect drive belt (also the 2): Inspect, not replace - cracking or glazing means it is aging, but a healthy belt stays.
B12 on your dash is three codes in one. B means replace the engine oil and oil filter and give the car a full mechanical inspection - brakes, suspension, steering, fluid levels, driveshaft boots, exhaust. The 1 means rotate the tires. The 2 means replace the engine air filter AND the dust and pollen (cabin) filter, and inspect the drive belt.
Every Honda Maintenance Minder code explained