transmission on 2006 Chevrolet HHR

Car is not shifting into high gear while driving. It stays in second. Possible cause?

Asked by for the 2006 Chevrolet HHR
You could have a transmission problem or possibly maybe just the in the shifter system. Is the Malfunction Indicator Light (MIL) on? If so, there's data and trouble codes stored in the controller and would help for diagnostic purposes. A mechanic with a scanner could read the codes and data.
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