Check Engine Light

Maintenance/Repairs
,
1

2007 Mini Cooper S - Engine light stays on but when I have it checked no codes show up. Any answers or suggestions???

2

There might be a problem with the light circuit inside the ECU causing the issue. You might try resetting the ECU to see if that changes things. Leaving the battery disconnected or removing the fused power to the ECU for about a half hour should reset it if you don’t have another way to do that. If the trouble still occurs after a reset then I would have to think the ECU is causing the trouble. I think most systems use a switched ground through the ECU to activate the lamp.

3

@cpap

Another possibility:

The guy retrieving codes is using an aftermarket scan tool which can’t retrieve the Mini specific fault code.

You may need a Mini scan tool or at least a factory-level aftermarket scan tool.

4

Very good point @db4690. That makes a lot of sense.

5

Mini = BMW = proprietary diagnostic equipment may be needed to read the codes… I’m sure, for a hundred bucks, any Mini dealer can tell you why the light is on…

6

At a minimum, definitely find out what the DTC code is that is turning the CEL on. Some can be ignored for a while, but some need to be addressed quickly or you may face expensive repairs due to a damaged cat. It’s a good investment to take the car to a shop who has Mini experience and can properly read the codes. It would be highly unusual for the CEL to come on and stay on w/no stored codes.

7

Don’t disconnect the battery.

Your vehicle is listed as one that may require reprograming of computers/modules with a factory scanner to get them to work again. http://www.aa1car.com/library/battery_disconnect_problems.htm And that won’t be cheap.

Tester

8

where did you have code checked?

9

Go to a mini dealer, or a BMW dealer.

10

Thank you everyone, went to a shop with a factory scanner. All is good #2 coil had a problem. Back in action.

11

Congratulations

12

Good on your for getting that coil problem fixed @cpap . A coil problem , if it causes misfires and results in a rich mixture of unburned fuel out the exhaust manifold, is one that can damage the cat if left unfixed for too long.