Go to auto zone and have the codes read for free. They will also look up the meaning of the code for you, but be careful about taking their advice on how to fix the problem. If you have an older Focus, buy a code reader on eBay for approx. $50.00 USD. (OBD-II) because you will need it a lot. The Check Engine light is always related to something in the emissions control system, e.g., a bad sensor, a leaky vacuum hose, etc. Other auto parts stores may also read the codes from the computer for free. Do not pay a mechanic just to read the code. You can try clearing the code from the computer and waiting to see if it comes back. The computer connection port is below the steering wheel, to the left, behind a little plastic cover.AnswerAutozone is NOT the answer.
Pull the codes from the computer, match the code to the troubleshooting procedure, follow the procedure to find the source. Repair the source, light will go out if that was the only problem. There are "monitors" or self tests the computer runs the car through a drive cycle, if a problem occurs, it may not run all of the self tests until that problem is taken care. Therefore, another problem may exist. It is emission related. OR hook up a scanner that is capable of clearing codes, and hope that none are still active.AnswerMine was a oxygen sensor
The check engine light is a " picture " of an engine , just to the left of the engine temperature gauge
Check the thermostat first. I had an intermittent overheating problem on my 02 for almost a year, changed the thermostat and it never happened again. If that doesn't work, secondly I would check the water pump.
i just changed my batterys out on my truck now my check engine light is on?
Then you may want to have a mechanic check it out.
The check engine light on a 2002 Ford Focus can be reset by disconnecting the battery for 1 to 2 minutes. This resets the vehicle's computer and clears the light.
Did you reset the light? I don't know what gasket you changed, but undoubtedly that was not the problem. The check engine light comes on when there is a problem with the emissions system.
Have vehicle scanned to determine the problem
It comes on when the engine computer detects a malfunction and sets a code.
There are pages and pages of things that can cause a check engine light. You need to have it checked with a scantool. Then the code can be diagnosed and repaired.
changed battery engine light stays on
Your check engine light will not come on because your coolant needs to be changed. The only way to be totally sure why it is on you should get it checked with a computer at a dealer or service station. The check engine light may come on if it is over heating because there is no coolant in it but not if it just has to be changed.
Could Be Both SOHC Or DOHC Check Your Engine