Check Hybrid System

[TonyHSD]

3 hours ago, Wolds White said:

Toyota Auris reg 2013. I got “Check Hybrid System” with yellow warning triangle. Last week I got the AA out as I was unloading exhibition material in a venue and left the boot open for 20-25 mins. The interior lights drained the 12v battery. The car wouldnt start just a clicking noise. The AA man said a big portion of his work is turning out to Toyota Hybrids with the same problem. The following week I get the above error. Took it to Vantage Toyota in York. They said they had never seen the error and stripped the car down. They said it was 6 hours work but only charged me for 3. With a new front tyre and wiper blade cost me £450. Travelling back from Whitby I got the error again. I saw on a forum that by disconnecting the negative terminal on the 12v battery in the boot, it clears the error. I tried it and it worked! So maybe my battery is on its way out after I drained it last week?

Hi, 

The interior light can’t be responsible for draining your 12v Battery in 20-30 minutes., it can help but really your 12v Battery it seems already dead, espoused if it’s the original one. 
Check hybrid system error can be non hybrid Battery related issue. This needs to be confusing by running a diagnostic. You can buy an obd 2 adapter and use app on your phone check and clear any error codes but you will have a picture of what is not right. Disconnecting a 12v battery to reset your ecu will only eventually clear the codes but they will come back again shortly after you start driving. 
For the hybrid battery,  depending on mileage it is very likely to be dead and you may need a new hybrid battery too. 
Here my two posts about batteries In Auris hybrids and how I replaced them by myself. May help you deal with yours. Good luck 👍