The 420 code means you need the catalytic converter replaced. The TCS means Traction Control System. The green key is the theft system. Both lights MAY have nothing to do with the car shutting off Sometimes those lights will display when something elese makes the car stall. Perhaps a faulty crank sensor or the cat is so clogged its stalling out the car.
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The 420 code means you need the catalytic converter replaced. The TCS means Traction Control System. The green key is the theft system. Both lights MAY have nothing to do with the car shutting off Sometimes those lights will display when something elese makes the car stall. Perhaps a faulty crank sensor or the cat is so clogged its stalling out the car.