While driving, the D light blinks occasionally after acceleration uphill or when on drive, but not in motion for long, such as in short traffic. I have changed the ATF but not yet. I am convinced the diagnosis may not read if the blinking is inconsistent. Others suggest it may have something to do with speed sensors, not sure which one. The effect is that when blinking, the car while still in motion maintains appropriate speed but struggles to pick speed once you slow down.
Hi and thanks for contacting YourMechanic. It looks like the D light is coming on for a couple of reasons. One, the shift position sensor could be failing causing the computer to not know what gear the transmission is in. The other could be a gear solenoid that could be going out with too much resistance. Check the harness to the shift sensor on the transmission for any debris or corrosion and check the harness to the transmission for any burned wires or disconnections anywhere. I recommend replacing the shift sensor first and rechecking to see if the D light still blinks. If the light still blinks, then I recommend changing the gear solenoid. That should take care of the problem. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect your vehicle for you, and make or suggest any repairs as needed.
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