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Q: no communication with computer and the security light is on.

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hi, the answer to the scan tool is yes its hooked up and the power is on it reads like this yes means it has communication no means it says no communication as follows engine no, abs no, trans no,airbag yes, body control no, instrument yes,key fob yes, theft module yes, tire module yes,. The security light went off after a few seconds when we put it to run and the scanner said the key was programed so we didnt reprogram it. We disconnected the battery for 15 min and reconnected it the engine started and runs smooth still no communication with engine, security light is on while running gauges going crazy occasionally error light was on by odometer, put it into drive the error light went away and there was communication with engine, shift into drive again lost communication with engine gauges screwing up again flashes error in odometer

My car has 104000 miles.
My car has an automatic transmission.

Hi there. The security is active and the computer will not communicate with the vehicle as it is being turned off. Remove the battery cable for 13 minutes and during that time, operate everything in the vehicle, even though there is no power. This will drain all capacitors in the computer and cause the security system to reset. Then hook up the battery and put the key in the driver door and lock and unlock the door 3 times. Then start the engine and watch the gauges. Now, you should be able to put the digital code reader on the computer and view the information. If the reader is not working for specific preferences, the select the vehicle as a generic operation and the reader will display the vehicle information. If you need further assistance with getting the code reader to work, then seek out a professional, such as one from Your Mechanic, to help you.

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