Hi so just been re-setting the warning lights that suddenly came on : Hybrid system, slip indicator, brake system warning and service engine warning. I re-set by disconnecting the 12V battery and re-connecting after 30 minutes. It was fine for a few days, then yesterday came back on and I did the same thing. Its booked for a service next week at a main dealer but can anyone shed any light on this especially as it was struggling to accelerate above about 30 mph suddenly too?
My wild guess is your hv battery is bad. When it is low the engine has to do all the work and the Adkinson cycle engine depends on electric assist for reasonable acceleration. Under these circumstances I would expect the battery bar graph to be low. There are other faults that cause a "limp home" reduced power mode such as a failing inverter or possibly a failed water pump or battery blower. The brake boosters are flawed on these models as well. A low cost bluetooth obd2 adapter and a Dr Prius phone app can tell you more but won't be as definitive as a dealer and won't fix it. http://www.bit.ly/ObdTwo
Hi so Toyota dealer confirmed what I feared during a full service: hybrid battery on its way, £1850 to replace, has been ordered, fit in 2 weeks (used battery/recon is about £1200 on ebay etc inc. fitting but getting new one) irony: if it was UK model-(its a Jap import)-be covered by warranty. On the positive: got car during lockdown last year so good price, despite these extra costs, still in positive money wise. Most cars I've had lost money on so its not all bad news.... PS warranty for new battery is only 1 year.
The good news is you will have a new Toyota hv battery that will easily last seven or more years. Your miles per liter will increase and the resale value of the car will also rise with a receipt showing a new oem battery in 2021.