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Q: Replacing the PCM

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I keep getting a "Transmission Over Temp" warning. I took it to the dealership and they said the transmission is fine but the PCM needs to be replaced, at a cost of $1000. I have found a site that sells PCMs with a warranty for $199. I need to know the location of the PCM and if you agree with the diagnosis. Thanks!

My car has 80000 miles.
My car has an automatic transmission.

A: I would not agree with the PCM replacement,...

I would not agree with the PCM replacement, especially because the Transmission Over Temp sensor is in the transmission itself and sends signals to the transmission control module. The transmission module sends signals to the PCM and BCM to turn on the light in the dash.

Only a thorough check of the readings from the transmission's temperature sensor to the transmission module would tell you if the sensor is defective or if your transmission is really running hot. Take you vehicle to another dealer to have it tested. Also, check to see if your vehicle PCM is under the recall to have it reprogrammed for free. This may fix the problem with your PCM if it is at fault.

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