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Hi,

When I started the car one day there was a noise like from loose belt then despaired? I kept driving my car and suddenly the engine stop. I waited half an hour and then I was able to start again but even if I press the gas to the floor I couldn't go more than 40 km. Obviously something was seizing ( suspected alternator or a/c compressor).
Also the key light is ON. I towed the car to my mechanic and he said that the catalytic convertor was red and the car was working reach. Then he tried to connect the diagnostic tool to read the code from my computer (the engine light was on) and the message was 'Check Connector'.
He tried on different car and the diagnostic tool was working but does not want to connect on mine. I'm sure it works because we used it three months ago when we changed the timing belt and was able to read the codes from the car.
Please, give me some suggestions and possible solution.

Thank you in advance,