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Q: TCM causes engine light to come on, but no transmission problems - is it safe to drive it?

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Nearly a year ago my car engine light came on. It was diagnosed by the dealership to be a fault in the TCM. They recommended replacing it which I had them do. They replaced it with a used module as the part can no longer be obtained new. It had a two month warranty. At 3 months the engine light came on. I was still have no other sign of any transmission problem, just the light. I have been driving it since, for about five months, with no transmission issues experienced. Is it safe to drive the car? My car now needs about $1200 in other repairs (oil pan and gasket and front brakes). The only thing stopping me from making the repairs is the TCM issue. Can I just continue driving it like that or is it really not a good idea? I just forsee putting in module after module and having the same fault reoccur over and over.....

My car has 160000 miles.
My car has an automatic transmission.

The first thing I would do is scan the vehicle for codes to determine if the TCM is still the issue. If codes for the TCM appear, depending on the code and the problem, you may be fine to drive that away. There is no way of telling how long the transmission will last, so it is a gamble to have the other repairs done. I would certainly get the brakes done as this is a safety issue, and get roadside assistance in case your vehicle’s transmission decides to fail unexpectedly. If you would like to have this all checked, a professional from YourMechanic can come to your location to inspect the car for you and recommend the correct actions.

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