# Computer disconnected when battery was undone. How long do I need to drive the car before the computer connects again? Trying to take the emmions test and they told me that the computer was disconnected when we undone the battery. Just need to drive it till it resets. How long will that take

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### Anonymous

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Just take it on a nice long drive about 20 minutes long three seperate times giving it a chance to cool down in between drives (takes about an hour to cool). It could take as many as three nice long drives known as a DRIVE CYCLE. Its when all the systems that the computer controls have a chance to reach the temperature they operate at and tell the computer that they are in fact working.(the oxygen sensor in the exaust pipe needs to reach 600 degrees before it turns on) sometimes the computer needs to see that its working 3 CONSECUTIVE times in order to give it the "ok". hope this helps. -J

Posted on Feb 05, 2010

### Anonymous

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Sometimes a few days, starting and running it a few times a day. It could take a week or more. It depends on how many driving cycles and miles. You should run it long enough each time for it to reach full operating temp.

Posted on Feb 05, 2010

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