Gen 2 Cold Start Ful Gauge Issue

[T3Dan]

I have a new issue with my 2005 Gen 2 Prius T3. The car is unmodified.

On starting from cold, the fuel gauge registers as empty and the main warning light (red triangle) displays along with the rest of the usual orange warning lights. This seems to clear after a few seconds and the issue does not repeat after the car has been driven for a bit - starts up normally.

I don’t have the ability to read fault codes but wondered if this was a familiar issue to anyone?

[T3Dan]

Looking through the forum, I wonder if this could be a sign of the 12v Battery being on its last legs? It was replaced the year before I bought the car so would be 5-6 years old now.

[Catlover]

The Battery is old enough to start causing problems, but how about you ask a garage to test the Battery?

[T3Dan]

Battery confirmed to be goosed, not too surprising given the age. Halfords have replacements in the £70-£90 range but having not replaced the 12v before, does a anyone have recommendations for a replacement unit? 

[Phil T]

Auto express tests recommend Exide X-tra plus back in 2007 still highly rated odyssey extreme in an American review

[Ancient Nerd]

Get the correct Battery from Toyota. I'm fairly certain that it is a gel Battery, like the original.

The Battery for the Gen 2 is in the boot. So if the car is rear-ended and the battery cracks, then a conventional battery is likely to spray the occupants with battery acid. Not a nice thought.