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Q: Safe Mode is active on my truck.

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How or what do i need to do to get my safe mode off my truck. I got told that my truck was in "safe mode". and its just until i do fix my truck a little more and also i may need a transmission speed sensor but that all i know what i may need anymore suggestions?

Wont got into 3rd or 4th gear or above but will go to 1-2nd no problem but really high revving when im going about 34-40 mph. when i turn off over drive there in no revving but still wont go into higher gears more than 2nd. maybe 3rd its hard to hear or feel clicking in if it does go to 3rd gear. and for now im just goes to school work then home so im not going higher than 50 mph. but the highest ive gone while my truck was like this was 80 but my motor sounded like it shut off then back on in about a 3 sec difference. so need some kind of advice or tips on what stuff or what i need to do to put my truck to its original self again.

My car has 1287000 miles.
My car has an automatic transmission.

Hi there. Your vehicle should have an AODE or 4R70W transmission. In this transmission, in the event there is a power loss to the transmission or if the computer shuts off the power to the transmission, the default gear is 2nd, which works with no power. This is called ’Limp Mode’. Remove the harness to the transmission and check the pins for any voltage readings. If there is no voltage readings, then check the voltage on the harness to the transmission shift sensor and the vehicle speed sensor in the output shaft housing. If there is voltage present, then check the sensors for resistance. If the resistance is too high or if the meter reads OL meaning out of limits, then the sensor(s) need replaced and the battery cable removed to reset the computer to put the transmission back into service conditions. If you need further assistance with your vehicle stuck in limp mode, then seek out a professional, such as one from Your Mechanic, to help you.

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