2009 Yaris cranks but won't start

[sinead]

Hi everyone, I'm hoping someone could help me figure out what has happened to my car.

I have a Yaris, 2009 with 265,000Km. I was driving to work, stopped at the traffic and the car stalled. The car was cranking but would not start, all warning lights were on. The lights and radio still work.

Brought it to a mechanic, they thought it was a crankshaft sensor issue. New sensor put in and still won't start. It was swapped out for another sensor and still wouldn't start. The following were checked and were fine; battery, alternator, ignition fuse, spark plugs, immobilizer, starter relay. Car is getting plenty of fuel and still returning an error code for the crankshaft sensors.

Before all this happened the car was fine, there was a P0420 code before but mechanics said that wouldn't cause this issue. I used cataclean too and the car was driving perfect.

Has anyone been through something similar? What was the solution and what do you recommend?

[komichal]

- Try the second key for the car. The immobilizer unit inside the key might be dead.
- Try disconnecting both oxygen sensors (there are connectors in engine bay). If any of them is short-circuited, I could imaginge the ECU could refuse to start. P0420 sometimes refers to bad oxygen sensor rather than catalytic convertor (though they have their own codes)
- Try all fuses, one by one, if they are OK. Not just the ones in the engine bay, but also under the steering wheel.

These are just wild guesses. Worth a shot though.

[komichal]

I am pretty sure there is a passive RFID in the key. Trying out a second key is really a thing.