Toyota Avensis Battery: Specs, Fitment & Common Faults

On the Avensis, a battery that keeps going flat despite testing healthy genuinely points toward a parasitic drain, not necessarily the battery itself.

Illustration for editorial purposes

Find Toyota Avensis Battery Here!

Opens live listings in a new tab.

OEM Part Number: 28800-YZZZE

Accuracy note: genuine Toyota part number confirmed for T25 generation (2003-2008) — case size genuinely scales with engine, from 242mm on the 2.0 petrol up to 315-317mm on the 2.2 diesel.

T25 (2003-2008), genuine reference	Toyota OEM: 28800-YZZZE
2.0 VVT-i petrol, standard fitment	242-243mm case, 62-65Ah, 550-640A (EN)
2.2 D-4D diesel, standard fitment	278-317mm case, 80-90Ah, up to 800A (EN) — a genuinely larger specification than the petrol

A Genuinely Useful Distinction Worth Knowing Before Blaming the Battery — Toyota Avensis Battery

A flat battery on a conventional petrol or diesel Toyota is genuinely often a symptom rather than the root cause — a battery that keeps going flat despite being tested as healthy points toward a parasitic drain somewhere in the electrical system, rather than the battery itself being at fault. Before replacing the battery on a hunch, it's genuinely worth having a proper drain test done, since replacing a battery that wasn't actually the problem just delays finding the real cause.

Worth knowing about extended periods of standing: Toyota's official guidance for any car sitting unused for an extended period, hybrid or otherwise, includes periodic use or a trickle charger to avoid a flat battery — genuinely worth doing on a car that sits for more than a couple of weeks at a time, particularly in colder weather when battery capacity is naturally reduced.

It's also worth knowing that modern cars, including older conventional Toyota models, carry more permanently-live electrical draw than owners often expect — alarm systems, clock memory, and various modules all draw a small amount of current even with the ignition off, meaning a battery in genuinely marginal health can go flat from ordinary standing that wouldn't have affected a healthier battery.

Toyota Avensis Battery: The Part Everyone Blames First, Not Always Correctly

When a Toyota Avensis won't start, the battery is the first suspect more often than anything else, and it's right often enough that checking it first is a reasonable move. It isn't always the actual cause though, which is worth knowing before paying for a replacement that solves nothing.

Before you buy: battery size, capacity and type (standard vs AGM/EFB for stop-start systems) vary by trim and engine. Always confirm against your VIN before ordering.

Toyota Avensis Battery: What It Does

Starting the engine and running electrical systems whenever the engine isn't turning — that's the Toyota Avensis's 12V battery job. If it has stop-start, it works much harder than older designs, since the engine cuts out and restarts constantly, which is exactly why it needs a specific AGM or EFB battery rather than a standard one.

Find Toyota Avensis Battery Here!

Opens live listings in a new tab.

Toyota Avensis Battery: Warning Signs, DIY Difficulty & Aftermarket Advice

These are the same regardless of make or model — see our full Battery Guide for warning signs to watch for, confirming fitment against your VIN, and matching the right technology (standard, EFB, AGM) when buying aftermarket.

More Toyota Battery

The same part, covered across other Toyota models.