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The issue you are experiencing is a safe mode for the transmission. When the computer notices an issue with the transmission it will convert to safe mode (no O/D). Normally this is caused by a faulty sensor or solenoid. The only way to pinpoint the culprit in this situation is to run a diagnostic scan on it using proper transmission diagnostic equipment. The trouble code will then point out the culprit which like I said is most likely just a faulty sensor.
Sure no problem. I have created an estimate for you to look over below. It is for running a diagnostic test on the transmission & replacing the shift control solenoid (labor + parts). This is an estimate for the dealer so you may find it a bit cheaper at local tranny shops. Of course I am not saying the shift control solenoid is the component at fault here, this is simply for reference as other solenoids and sensors should be similar.