Chrysler Repair: check engine warning light, unnecessary air pollution, chysler pacifica

Question
What does it mean the the ! warning light is on in  the dash of my 2004 chysler pacifica

Answer
Hi Patricia,
The warning light 'on' means that the engine computer has noticed a problem which causes the engine to put out unnecessary air pollution and is urging you to find out what the problem is and correct it. You can likely do that with the ignition key: "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. In most models the odometer will then change from showing the mileage to instead showing a 4 digit number, prefixed by a P, which is called a 'fault code'. Or several such numbers. Note the numbers and send me a follow-up question telling me the numbers and we'll go from there. If that doesn't happen, then go to an Autozone parts store (or similar nationwide franchise store nearby) because they are likely to give you a free code readout using a plug-in device that mates with a socket under the dash by the steering column. That process too will give you the fault code number which we need to know to make the appropriate correction. Tell me which size engine is in the vehicle, please.
Roland
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