2019 XLE Not Starting

My Prius XLE has got 148k miles on it and has been acting odd.

At first I went out to go use it and it wouldn’t start but horn, lights, and all came on just fine. Used a jumper and it cranked right up. Took it to the shop near me and got a new battery. My battery was showing 11.7 and was 2 years old from Toyota dealership. Car cranked right up no issues.

A couple of weeks go by and I’m driving to meet some friends, about 45m into the drive I pull into a place to get some food. When I come back out, my car won’t start again, same as last time. This time jumping doesn’t help. I looked up how to go into maintenance mode which worked and drove home.

For the next two weeks it has no more issues again but I finally decide to take it to the shop again to get checked. They found nothing but a code for the brake sensor. They swapped out the sensor and then called me to let me know the car is again not cranking despite the sensor change.

What could be causing this? My guess is something brake related (my brakes were recommended to be replaced like 8 months ago tbh). My next concern was the EV battery. Lastly, I street park and someone took out my mirror a year ago or so and I never got it fixed, could the exposed wiring or something be draining my battery or causing the start system to not crank up?

 

This is how I was able to get home after being stranded an hour from home. Option 2 did nothing but option 1 got it started. It worked fine for the next week after that and ran fine. Took it to a mechanic anyway but they found nothing other than a brake sensor code on their Toyota scanner device. They replaced the sensor and tried to take it out of the garage and the same issue occurred. Couldn’t find anything else outside the sensor.

My only other thought was still brake related as I know my brakes are going/gone “bad”. I was told by another mechanic 6 months ago my brakes pads were needing to be replaced badly and hadn’t done it yet (Financial issues came up due to an injury I sustained)

Hey financial hardship happens. I make decent money but had to have surgery that cost ~$80k. Money is tight right now. Key fob was first thing I checked and replaced batteries in. Fob works fine and has given that message before when it got low. No such message now. Simply goes into accessory mode only unless I use the emergency/maintenance start function (parking brake engaged, accessory mode, and then hold start for 15+ seconds)

My mechanic has a high end scanner (~$4,000 when originally purchased) and it only showed a brake sensor code.

When I picked the car up to try somewhere else with a specified Toyota specialist, the mechanic said when I left it with him on Friday morning that they didn’t get to it until Monday and the new battery (was maybe a week old) had died again and he had to put it on the charger to get it into the garage put it cranked up and went in. After they replaced my sensor and tried to pull it back out, same thing, wouldn’t start again (battery read full charge). Had to use the emergency start/maintenance mode to get it out. He didn’t charge me anything for the sensor or for holding that car for so long as he felt bad for not figuring it out (he’s been my mechanic for ~15 years and has the most respected shop on the area.

He gave me the number of a garage run by a guy who is known as Toyota specialist (worked for Toyota for over a decade before starting his own business). Described everything to him as did my mechanic and he’s at a loss for what could be the issue. Said I could take it to him anyway and he would do some digging and wouldn’t charge me unless he figured it out.

It can force start your car in an emergency. I found it while stranded and trying to troubleshoot the issue myself with limited tools. Basically you apply the parking brake, put the car in accessory mode, hold the start button for 15+ seconds.

That got me home. Next day I went out and the car cranked up and started no issue. I used it for most the next week no issues and figured I should take it anyway to get checked. Dropped it off on a Friday and on Monday they went to move it into the garage and the battery (12v had died despite being maybe a week or two old). He charged it up and got it into the garage where they checked it with a scanner that does Toyotas. Only code to pop up was brake sensor. He replaced it (no charge) and went to pull it out… it did for him what it did to me. Battery (12v) was fully charged but would only go into accessory mode or you could force it to start with the emergency/maintenance mode listed in the manual.

He gave me the number of a Toyota specialist and we all three talked together over the phone and he is also lost on what it may be. Said I could send it to him and he’d try to troubleshoot it and not charge me unless he fixes it. He worked for Toyota for a decade before starting his own garage, everyone here send their Toyotas there as we have no dealership unless you drive or tow over an hour away.