P0631 Trouble code – VIN not programmed or mismatched – TCM

What is the P0631 fault codes? VIN Not Programmed or Mismatched – What is the TCM error code description? How can you fix the P0631 error code? What are the causes and symptoms of the P0631 error code?

What is the P0631 fault code? What does it all mean?

P0631 is a code that indicates the transmission control module, (TCM), does not recognize the 17 character vehicle chassis number (VIN).

Automakers assign a special 17 character number called “VIN” Every car they produce. This number is also known as the chassis number and it is a unique type of vehicle identification number. This sequence of numbers and letters identifies the country of manufacture, year of manufacture, make, model and engine type of each vehicle. The serial number of the vehicle is represented by the six last digits after the VIN. The VIN must be programmed into the ECM/PCM to produce all OBD-II-equipped vehicles. VINs may also be programmed in other modules such as the TCM on some vehicles. This is done to prevent theft or alteration of the vehicle’s module and/or VIN.

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Without fitting the vehicle’s programming, system controllers can’t be interchanged between vehicles. This application can cause vehicles’ odometers to display incorrectly. It is necessary to reprogramme the vehicle’s VIN and mileage if the ECM/PCM has to be replaced. The vehicle must be programmed so that it can recognize the VIN in TCM.

Every time the ignition switch switches on, the ECM/TCM/PCM performs self tests and searches the VIN. If the TCM can’t find or recognize a VIN, the code P0631 is issued. The vehicle will not start in such cases.

The P0631 fault code can affect vehicles of all makes and models, including but not limited to Fiat, Jeep Land Rover, Suzuki (Ford), Ford, SsangYong. Acura, Chrysler, Dodge. Crown Victoria. Toyota.

What is the P0631 Fault Code and Why Does It Happen?

Here are some reasons why P0631 should be set.

– Extended power outage to the TCM
– Dead battery
Unprogrammed switching between vehicles of TCM
– TCM programming error
– Connectors and cables problems
– Defective TCM

What are the symptoms for P0631 Trouble Code

You may experience the following symptoms if your vehicle has the code P0631:

– Illumination at the check engine lights
– Vehicle does not start at all
Engine stalling
– Incorrect or irregular gear shifting of the gearbox
– The transmission does not change or stay in any gear.
– Vehicle security systems may be activated
– Setting related fault codes

How to Fix the P0631 Fault Code

There are several repairs that can resolve the P0631 fault code.

Repair or replace any damaged, disconnected, corroded or shorted components, connectors, and cables.
– Reprogramming TCM
– Replacing an invalid or incompatible TCM
– Replacing dead batteries