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Q: Drove through a puddle of water and now the car won't start

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I recently bought car used and it had no problems. It has been raining a lot where I live. I was driving home and exited the roadway, and went into a big puddle of water. The car went almost all the way through the puddle, and then it turned off. I had to use the emergency neutral lever so we could push it out of the way. I was able to push the car the few remaining blocks to my house. Then, I tried turning the car back on but it says 'service transmission'. Is it a sensor or a safety switch that prevents more damage? Or is it something else?

A: In order to create a safe driving state and...

In order to create a safe driving state and prevent damage to the automatic transmission, the transmission control module (TCM) will force the vehicle into "limp mode". In this state, all solenoids and regulating valves are de-energized and the last engaged gear remains engaged.

In addition, the TCM maximizes line pressure and disables torque converter lock up. The TCM will keep the vehicle in limp mode and display the transmission warning light until the problem is rectified and the corresponding diagnostic trouble code (DTC) is cleared.

There is a good chance that water got into the sensitive electronics of your vehicle. Having a trained professional inspect your vehicle is the only way to determine the exact cause of your starting problem.

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