On 12/30/14 my car had 6 spark plugs and a gasket replaced by a GM dealershhip in response to the check engine light being on. An air induction service and a fuel injector cleaning service was also performed at this time. On 01/26/15 I had to replace the battery in my car. After replacing the battery the check engine light was on and has stayed on. I read elsewhere online something to the effect that when a car battery is changed your car has to relearn the emissions system and the check engine light might possiby come on but should go off after driving awhile. I have driven approximately 300 miles since the battery change and the car is running fine. However, thcheck engine light is still on. The GM dealership is in another town and I hate to make the trip to have it checked if I don’t really need to. HELP and thanks!
Take your car to an Autozone, or the like, and they will read the code(s) that turned on the light. Post the results here.
I think I recall there’s been other posts here w/this same problem. Not sure which vehicle is involved in those posts. But the sol’n was that this is normal for that type of car and to take the car to the dealership, where they’ll have the proper manufacturer scan tool which will turn off the light for you.
You might ask why changing the battery would turn the check engine light on. That’s a very good question. You may have already hit on it, the computer gets confused when the battery is disconnected. Some cars won’t even start after the battery is disconnected, and have to be towed to the dealership to get them back on the road. So think positive, you are ahead of the game already.
Since you live some distance from the dealership, give them a call at a time when they probably won’t be very busy and maybe the service rep will already know about this from other customers coming in w/the same problem and can help you over the phone.
The article below states that on some vehicles a false warning light can come on when the battery is disconnected.
http://www.aa1car.com/library/battery_disconnect_problems.htm
I’d drive the vehicle for a while to see if the Check Engine light eventually shuts off. After all, there’s a lot of stuff the computer has to relearn again.
Tester
I’m guessing the plugs and plenum gasket were replaced
Perhaps the light is still on, because there is still false air
time to read the codes, and post them
If it’s the exact same code as earlier, time to go back to the dealership
Maybe the code was cleared after the initial repair, but they didn’t actually verify the repair. And it took a couple of “bad trips” to turn the light on again
it’s possible the check engine light is on because of battery replacement
But in my mind, it might be related to the initial repair
There’s another possibility . . . on some GM cars, when you clean the throttle body, you must relearn the throttle with the proper scan tool, or else you’ll get strange idling and a check engine light. I’ll bet you that “air induction service” included a throttle body cleaning. Maybe somebody forgot the relearn, if it applies
After reading your “greatly informative/helpful replies” I decided to bite the bullet and make the trip to the dealership. They hooked it up and found no codes so just turned off the check engine light. It took 5 mins tops (nocharge-YAY) but 45 mins travel time each way…wish I had one of those machines. Thanks to everyone who replied.
@Jeanneb1 Umm . . .
If the check engine light was still lit up, when you arrived at he dealership, there were codes
They may not have been current codes, but there were codes
It’s a shame the dealer didn’t tell you what codes there were, because we would have offered our opinions, as to why they were generated in the first place
At least it was free . . . !