tnixa

My wife and I both drive our 5series but she is the primary driver and loves the car. While we were on vacation I agreed to let my mom borrow the car for a few days (after getting permission from my wife). The SES light came on while my mom was driving the car and now my wife is thinking she did something to "break" the car. The car runs the same as before and iDrive does not report any problems.

I poked around the forums and found a gas cap can cause the SES so I checked and it seemed a little loose but I'm not 100% sure if it was loose. I tightened it to the click and drove it around for a few miles but the SES is still on.

We got into a huge fight over this as I don't believe my mom could have done anything to cause the SES to come on (outside of not tightening the gas cap enough). My wife thinks my mom was driving hard or messing around with some buttons or did something to cause the SES. Needless to say, I am never going to let my mom borrow the car again as it is just not worth it having something like this happen and fighting with my wife.

Couple questions...

1) Hopefully the issue is the gas cap and the SES goes off soon. How long would it take for the SES to go off or would the dealer have to reset it? Or can I reset it?

2) Please back me up and tell me there is no way my mom "broke" the car.

528canyonrot

My car has its own light for a (loose gas cap) I infer yours is probably the same.
If you dont have your own obd2 code scanner take it to autozone and have them pull the codes.
Tell your wife to cool her jets
Report back how that goes

ponnu

Did your mom by mistake fill the car up with regular gas while she was driving? people tend to do that accidentally whenever they borrow cars which might require high octane gas.

tnixa

I told her the mid octane (~89) would be fine as that is what we usually put in. Will the SES go off for low octane gas?

528canyonrot

Stop wasting your time with (guessing) what your codes are, Go get your codes pulled.

tnixa

Found out it was the P0442 code. Hopefully loose gas cap was the problem. I reset the code so hopefully it doesn't come back.

KyleB

likely a loose gas cap, your mom was probably trying to do you a solid and thank you by putting gas in the car.

reset OBD and check for fault code P0666, faulty wife.

ilicboris91

You run 89 in your car? The one with 10% ethanol?

b00sted415

I thought these cars require you put in 91 octane?

tonyb635

Yes they do, but I've ran reg, mid and hi in mine many of times. I don't normally use anything but hi. I've never experienced any issues from using the lower grades but I only do if if I have to. As for your cap, that’s the likely source. All it can take is not turning the car completely off and then releasing the cap. Most of the time I hear is supposed to go out on its own after a little driving. Now for something interesting. Two weekends ago, I drove to Charleston (200 miles) and departed after I filled up. It was raining like never before as well. The following morning when coming out to my car I noticed the gas cap was hanging on the side of the car. My first impression was WTF! I guess someone was trying to steal it... But after getting closer, I realized this was not possible as the locks were still engaged. This means I drove this distance without a cap on! I never got any warning of this at all.