I have 2005 chevy trailblazer Lt 4.2 4wd 6cilinders and my speedometer stop work on 2005 Chevrolet Trailblazer

My speedometer stop working and plug a little computer and now I have a code c0055 vehicle speed sensor circuit..and I need to know where is located this sensor

the sensor is in the side of trans at the rear,but it could be the circuit also
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I can see this is an old post, but this is probably an instrument cluster problem. Very common Gm problem.
You have to get a remanufactured unit and it will need flashed to the vehicle