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1999 Saturn SL2 reverse issues

My 1999 Saturn SL2, automatic transmission, will not go in reverse. All other gears are fine. The car does not jerk or anything when moving forward. Please Help!

One thing that has to happen to get reverse in your transmission is a dog has to disengage one of the forward gears and engage the reverse gear. After this occurs the hydraulic clutch (I think it is the second clutch) engages to transfer the power. The clutch must be okey as you are not having problems in the forward shifting.

You will usually hear a light click as the dog slides on the counter shaft; releases the forward gear; and catches the reverse gear. Have someone outside the car listen as you shift to reverse. If the click is not present, the problem is internal to the transmission so diagnosis by a transmission technician is called for.

Hope this helps.

I did some research on your transmission. I found out that the Power Control Module needs to see a Vehicle Speed Sensor reading of less than 5 MPH. If so the line pressure is raised using the pressure modulation solenoid to allow the second/reverse dog clutch to move. It was not explicitly stated but I suspect the PCM then commands second/reverse clutch to engage by activating the appropriate solenoid.

So the transmission technician will have to diagnosis the inputs to the PCM; the operation of the pressure modulating solenoid; the condition of the pump pressure capability, i.e. line pressure measurement in reverse; and whether the PCM is commanding the second/reverse clutch to engage.

It is nice to know what might be going on but you still have to have the skill, knowledge; and tools to narrow down the problem.