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Q: AT light on

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Took my car to my mechanic last week to get AC/ heating fixed. Next day the AT light was on. Checked transmission fluid, it was at a good level. Car seems to be driving fine, just the same.

My car has 150000 miles.
My car has an automatic transmission.

One of the most common causes for this light to come on is the transmission input speed sensor goes bad and the transmission module connector. If you have the system scanned you would get codes pertaining to the input speed sensor of the transmission. The sensor is in the top of the transmission under the battery tray.

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