Some problems with my 92 Maxima.

My speedo doesn´t work and the car sometimes locks in one gear and sometimes only shift down one gear when i kick down.

I ran the self-diagnostics and came up with the following errors:

Revolution sensor circuit
Speed sensor circuit
Line pressure solenoid valve circuit

I´m a newbie, can someone please explain what these things are and how to fix them/how much it will cost to fix?

The speed sensor is no problem, I know where it´s located and how to change it, but the other two?

I appreciate all help I can get.

Thanks!
John

 

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