Skip the auto shop - Our mechanics make house calls

Q: Replacing the PCM

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Motor swap

Hello. The coil pack is part of the ignition system and is of little consequence to what motor it is used on. A long block, which consists of the head and engine block assembled, is very versatile in terms of...

Q: AC blowing hot air after engine replacement

It sounds like your air conditioning has lost a charge. The refrigerant may have leaked, or they may not have charged the AC when they replaced the engine. I would have a technician come out and inspect your entire AC...

Q: Car keeps overheating. Making a steam noise. Coolant cartridge runs out about once a week.

You will need to trace the leak and repair whatever the issue is. To trace a cooling system leak, the best way is to run the car and watch for the leak. The most common places for a leak are...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...