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Q: My car is still acting up and the speedometer and odometer is not working.

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So before my car had the codes p0720 and p1529. I got both my input and output speed sensors replaced hoping it will fix the problem but it did not help. My car is still decelerating and going into failsafe mode when I try to reach 45mph and the engine light is coming on and off. I took it autozone and it just has the code p7020 but I just fixed it. The man at autozone told me to put more miles on it to erase the code from the computer. How am I supposed to do that if my speedometer and odometer isn't working? What should I do now?

My car has 206000 miles.
My car has an automatic transmission.

A: Hi there. First remove the battery cables ...

Hi there. First remove the battery cables both positive and ground. Go in the cab and operate everything, even though there is no power. After 12 minutes put the battery cables back on. This will drain all power to the vehicle and reset the computer. Now you can drive the vehicle around to relearn the computer. If he speedometer still does not work, then the instrument cluster will need checked or replaced. If you need further assistance with your speed sensor not working and the computer putting the vehicle into limp mode, then seek out a professional, such as one from Your Mechanic, to help you.

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